fix(appengine): address testing errors on helloworld, websockets, rails-cloudsql-mysql

[glasnt]

Resolves testing failures in some current open PRs

• build(deps): bump sinatra from 2.2.4 to 4.1.0 in /appengine/standard-hello_world #1494 appengine/standard-hello_world: allow all hosts for testing
• build(deps): bump rack from 2.2.8 to 2.2.11 in /appengine/websockets #1542 appengine/websockets: allow all hosts for testing, fix docker sandbox issue
• build(deps): bump rack from 3.0.11 to 3.0.12 in /appengine/rails-cloudsql-mysql #1540 appengine/rails-cloudsql-mysql: adjust whitespace on web page validation checks

• Please merge this PR for me once it is approved.

[snippet-bot]

Here is the summary of changes.

You are about to add 2 region tags.

• appengine/standard-hello_world/app.rb:22, tag gae_standard_quickstart
• appengine/websockets/app.rb:26, tag gae_flex_websockets

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