[DOCS] Fix elastic.co docs headers

Author: picandocodigo

docs/release_notes/70.asciidoc

@@ -6,7 +6,7 @@ This version contains the following changes:
 * Added `elastic_ruby_console` executable. It opens a console with the elasticsearch gems you have installed required.
 * Added macro benchmarking framework, available when developing. Use `rake -T` to view all available benchmarking tasks. 
 
-=== Client
+==== Client
 
 * Fixed failing integration test
 * Updated the Manticore development dependency
@@ -44,7 +44,7 @@ This version contains the following changes:
 * Update handling of publish_address in _nodes/http response
 * Add another test for hostname/ipv6:port format
 
-=== API
+==== API
 
 * Added the `wait_for_active_shards` parameter to the "Indices Open" API
 * Added the "Indices Split" API
@@ -129,7 +129,7 @@ This version contains the following changes:
 * Ensure that the :index param is supported for cat.segments
 * Ensure that the :name param is passed to the templates API
 
-=== DSL
+==== DSL
 
 * Add inner_hits option support for has_parent query
 * Add inner_hits option support for has_child query
@@ -153,7 +153,7 @@ This version contains the following changes:
 * Ensure that filters are registered when called on bool queries (#609)
 * Don't specify a type when creating mappings in tests
 
-=== XPACK
+==== X-Pack
 
 * Embedded the source code for the `elasticsearch-xpack` Rubygem
 * Fixed the `setup` for YAML integration tests

docs/release_notes/75.asciidoc

@@ -6,7 +6,7 @@
 - Specs have been updated to address new/deprecated parameters.
 - Ruby versions tested: 2.3.8, 2.4.9, 2.5.7, 2.6.5 and 2.7.0 (new).
 
-=== API
+==== API
 
 Endpoints that changed:
 
@@ -45,7 +45,7 @@ Endpoints that changed:
 - `termvectors`: `parent` parameter is gone.
 - `update`: `version` parameter is not supported anymore.
 
-=== X-Pack
+==== X-Pack
 
 Some urls changed internally to remove `_xpack`, but it shouldn't affect the client's API.
 

docs/release_notes/76.asciidoc

@@ -1,20 +1,20 @@
 [[release_notes_76]]
 === 7.6 Release notes
 
-=== Client
+==== Client
 
 * Support for Elasticsearch version 7.6.
 * Last release supporting Ruby 2.4. Ruby 2.4 has reached it's end of life and no more security updates will be provided, users are suggested to update to a newer version of Ruby.
 
-==== API Key Support
+===== API Key Support
 
 The client now supports API Key Authentication, check "Authentication" on the https://github.com/elastic/elasticsearch-ruby/tree/7.x/elasticsearch-transport#authentication[transport README] for information on how to use it.
 
-==== X-Opaque-Id Support
+===== X-Opaque-Id Support
 
 The client now supports identifying running tasks with X-Opaque-Id. Check https://github.com/elastic/elasticsearch-ruby/tree/7.x/elasticsearch-transport#identifying-running-tasks-with-x-opaque-id[transport README] for information on how to use X-Opaque-Id.
 
-==== Faraday migrated to 1.0
+===== Faraday migrated to 1.0
 
 We're now using version 1.0 of Faraday:
 
@@ -27,9 +27,9 @@ Reference: https://github.com/lostisland/faraday/blob/master/UPGRADING.md[Upgrad
 
 https://github.com/elastic/elasticsearch-ruby/pull/808[Pull Request]
 
-=== API
+==== API
 
-==== API Changes:
+===== API Changes:
 
 - `cat.indices`: argument `bytes` options were: `b,k,m,g` and are now `b,k,kb,m,mb,g,gb,t,tb,p,pb`.
 - `delete_by_query`: New parameter `analyzer` - The analyzer to use for the query string.
@@ -38,26 +38,26 @@ https://github.com/elastic/elasticsearch-ruby/pull/808[Pull Request]
 - `rank_eval`: New parameter `search_type` - Search operation type (options: `query_then_fetch,dfs_query_then_fetch`).
 - `search_template`: New parameter `ccs_minimize_roundtrips` - Indicates whether network round-trips should be minimized as part of cross-cluster search requests execution.
 
-==== New API endpoints:
+===== New API endpoints:
 
 - `get_script_context`
 - `get_script_languages`
 
-==== Warnings:
+===== Warnings:
 
 Synced flush is deprecated and will be removed in 8.0.
 
-=== X-Pack
+==== X-Pack
 
-==== New API endpoints:
+===== New API endpoints:
 
 - `ml/delete_trained_model`
 - `ml/explain_data_frame_analytics`
 - `ml/get_trained_models`
 - `ml/get_trained_models_stats`
 - `ml/put_trained_model`
 
-==== API changes:
+===== API changes:
 
 - `license/get`: Added parameter `accept_enterprise`.
 - `ml/delete_data_frame_analytics` Added parameter `force`.

docs/release_notes/77.asciidoc

@@ -3,17 +3,17 @@
 
 This version drops support for Ruby 2.4 since it's reached it's end of life.
 
-=== Client
+==== Client
 
 - Support for Elasticsearch version `7.7`
 
-==== Custom Headers
+===== Custom Headers
 
 You can set custom HTTP headers on the client's initializer or pass them as a parameter to any API endpoint. https://github.com/elastic/elasticsearch-ruby/tree/7.x/elasticsearch-transport#custom-http-headers[More info and code examples].
 
-=== API
+==== API
 
-==== API Changes
+===== API Changes
 
 - Clean: Removes up some deprecated endpoints: `abort_benchmark`, `benchmark`, `delete_by_rethrottle`, `nodes.shutdown`, `remote.info`.
 - `expand_wildcards` Whether to expand wildcard expressions to concrete indices that are open, closed or both. Options: open, closed, hidden, none, all. `hidden` option is new. It was also added to the following endpoints: `cat.aliases`, `cat.indices`.
@@ -22,7 +22,7 @@ You can set custom HTTP headers on the client's initializer or pass them as a pa
 - `update_by_query`: Parameter `slices` can now be set to `auto`.
 - `snapshot.cleanup_repository`: Parameter `body` is removed.
 
-==== New API Endpoints
+===== New API Endpoints
 
 - `cluster.delete_component_template`
 - `cluster.get_component_template`
@@ -31,15 +31,15 @@ You can set custom HTTP headers on the client's initializer or pass them as a pa
 - `indices.delete_data_stream` (experimental)
 - `indices.get_data_stream` (experimental)
 
-=== X-Pack
+==== X-Pack
 
-==== API Changes
+===== API Changes
 
 - `machine_learing.get_trained_models`: New parameter `tags`
 - `machine_learning.put_datafeed`, `machine_learning.update_datafeed`: Added parameters `ignore_unavailable`, `allow_no_indices`, `ignore_throttled`, `expand_wildcards`
 - `reload_secure_settings`: New parameter `body`, an object containing the password for the keystore.
 
-==== New API Endpoints
+===== New API Endpoints
 
 - `async_search.delete`
 - `async_search.get`

docs/release_notes/78.asciidoc

@@ -1,16 +1,16 @@
 [[release_notes_78]]
 === 7.8 Release notes
 
-=== Client
+==== Client
 
 - Support for Elasticsearch version `7.8`.
 - Surface deprecation headers from Elasticsearch. When there's a `warning` response header in Elasticsearch's response, the client will emit a warning with `warn`.
 - Typhoeus is supported again, version 1.4+ and has been added back to the docs.
 - Adds documentation and example for integrating with Elastic APM.
 
-=== API
+==== API
 
-==== New API Endpoints
+===== New API Endpoints
 
 - `abort_benchmark`
 - `benchmark`
@@ -33,7 +33,7 @@ Experimental endpoints:
 - `indices.put_index_template`
 - `indices.simulate_index_template`
 
-==== API Changes
+===== API Changes
 
 - `cat/thread_pool`: `size` is deprecated.
 - `indices.get_data_streams`: `name` is now a string instead of list, the name or wildcard expression of the requested data streams.
@@ -42,9 +42,9 @@ Experimental endpoints:
 - `snapshot.delete_repository`: New parameter `repository`, name of the snapshot repository, wildcard (`*`) patterns are now supported.
 - `task.cancel`: new parameter `wait_for_completion` (boolean) Should the request block until the cancellation of the task and its descendant tasks is completed. Defaults to false.
 
-=== X-Pack
+==== X-Pack
 
-==== New API Endpoints
+===== New API Endpoints
 
 New namespace: `indices`
 
@@ -59,7 +59,7 @@ New namespace: `searchable_snapshots`
 - `repository_stats`
 - `stats`
 
-==== API Changes
+===== API Changes
 
 - `machine_learning.delete_expired_data` new param `body`: deleting expired data parameters.
 - `machine_learning.delete_data_frame_analytics` new param `timeout`: controls the time to wait until a job is deleted. Defaults to 1 minute.