CI: Remove cache dependencies job to ignore save gradle dependency cache

With this job present, every tag related build tries to save the
dependencies in a cache, but, this functionality has been broken for a
while, the 'example:build' task is constantly failing on CI (see below).

Example Build (1.23.1): https://buildkite.com/automattic/
android-dependency-catalog/builds/189
#01922323-d7e6-4526-82b5-f5dca9e6ed6a

FYI: No matter, we have decided to not use this project for this
purpose, as as such to have a single dependency cache for all projects,
and then restore this bigger than needed cache per project, only to use
a specific set of dependencies per project. Instead, we decided it is
better for each project to have a scheduled job, either weekly or daily,
which will trigger this 'save_gradle_dependency_cache' script and only
save the dependencies that it really needs.

Author: ParaskP7

Diff for: .buildkite/cache.sh

@@ -26,11 +26,3 @@ steps:
     plugins: *common_plugins
     command: |
       .buildkite/publish.sh
-
-  - label: "Cache dependencies"
-    depends_on:
-      - "publish"
-    if: build.tag != null
-    plugins: *common_plugins
-    command: |
-      .buildkite/cache.sh

Diff for: .buildkite/pipeline.yml

@@ -1,6 +1,6 @@
 # Android Dependency Catalog
 
-This project is a shared Android dependency catalog for Automattic projects which uses [Gradle's version catalog feature](https://docs.gradle.org/current/userguide/platforms.html). It's also used for generating a dependency cache that we use in our CIs to speed up our builds.
+This project is a shared Android dependency catalog for Automattic projects which uses [Gradle's version catalog feature](https://docs.gradle.org/current/userguide/platforms.html).
 
 ## Table of Contents
 
@@ -10,7 +10,6 @@ This project is a shared Android dependency catalog for Automattic projects whic
 * [Releasing a new catalog version](#releasing-a-new-catalog-version)
 * [Naming conventions](#naming-conventions)
 * [Building locally](#building-locally)
-* [Dependency caching](#dependency-caching)
 * [Automatically updating dependency versions in the catalog](#automatically-updating-dependency-versions-in-the-catalog)
 * [Setting up your projects to automatically update the catalog version](#setting-up-your-projects-to-automatically-update-the-catalog-version)
 
@@ -61,7 +60,7 @@ See [Gradle documentation](https://docs.gradle.org/current/userguide/platforms.h
 androidx-recyclerview = { module = "androidx.recyclerview:recyclerview", version.ref = "androidx-recyclerview" }
 ```
 * `version.ref` refers to the version name from `[versions]` section in the [libs.versions.toml](libs.versions.toml) file
-* If this is a new plugin, add it under `plugins` section in [example/build.gradle.kts](example/build.gradle.kts) - make sure to add `.apply(false)`. This step is necessary because we use the `example` module to generate a dependency cache we use to speed up CI in other projects. We are able to automatically add the library dependencies, so this step is not necessary, but plugins need to be added manually.
+* If this is a new plugin, add it under `plugins` section in [example/build.gradle.kts](example/build.gradle.kts) - make sure to add `.apply(false)`. We are able to automatically add the library dependencies, so this step is not necessary, but plugins need to be added manually.
 * [Build the catalog & example projects](#building-locally) - if you get `Could not find {dependency}` error, make sure the repository for the new dependency you've added is included in [example/settings.gradle.kts](example/settings.gradle.kts)
 * Follow the instructions for [releasing a new catalog version](#releasing-a-new-catalog-version)
 
@@ -93,12 +92,6 @@ We'll need to iterate on our naming conventions, but here are some general guide
 
 **Note that `example` project does NOT use the generated version catalog from the `catalog` project.** Although this is not likely to cause a difference in practice, it's an important distinction to be aware of.
 
-## Dependency caching
-
-We use the `example` project to generate a dependency cache which is uploaded to S3 by CI and then used in several projects.
-
-Note that all libraries within the version catalog will be automatically added as a dependency to the `example` project, but the plugins need to be added manually.
-
 ## Automatically updating dependency versions in the catalog
 
 This feature is not available yet.