Fixes #23193

This was throwing `There was an exception - NameError(undefined local variable or method `hi_redis_conn' for #<ActionCable::SubscriptionAdapter::Redis:0x007fb1449e2b70>)` on unsubscribe.

First pass over parts of Testing guide

[ci skip] Add note about tsrange and timezone awareness to docs

rm changelog for unreleased changes fixes

remove `per_form_csrf_tokens` initializer from Rails API

Because the form is not in the Rails API,
`per_form_csrf_tokens` initializer I think unnecessary.

Based on https://github.com/rails/rails/pull/23167/files#r50507317

[ci skip]

- Grammar improvements
- Consistent usage of you or we in sentences
- Tests can have zero or more assertions. Its not mandatory to have one.
- Example for assert_send

[ci skip]

Remove action_cable_meta_tag when skip Action Cable

Add `config/cable.yml` to list of default files in Rails generator

Fix ActiveRecord::Relation#cache_key for loaded empty collection

Fix `ActionController::Parameters#==` bug

See bug #21032.

add application_mailer.rb to template of mountable engine

[ci skip] fix #23157

This is a similar case to wanting ot use bind params for limit and
offset. Right now passing a range grows the amount of prepared
statements in an unbounded fashion. We could avoid using prepared
statements in that case, similar to what we do with arrays, but there's
a known number of variants for ranges.

This ends up duplicating some of the logic from Arel for how to handle
potentially infinite ranges, and that behavior may be removed from Arel
in the future.

Fixes #23074

Fix warning introduced in API response fix

- Fix warning introduced in https://github.com/vipulnsward/rails/commit/77acc004efad07dfd4d4f83be14ef897968a3fd9 when fixing API  responses.
- render :text is deprecated, so added an assertion for it.

updating secrets.yml template to use rails command instead of rake

Improve Docs for ActionController::MimeResponds#respond_to

Re-add ActionController::ApiRendering

insert newlines into code samples in Upgrading section of Asset Pipeline doc

[ci skip]

- Fixes bug #23142.
- Bug was occurring only with ActionController::API, because `_process_options` wasn't being run for API requests, even though it was being run for normal app requests.

Fix marking of custom routes for Journey

Response etags to always be weak: Prefixed 'W/' to value returned by Act...

Small doc update per RF [ci skip]

Add CHANGELOG.md entry for #22950

[ci skip]

The Mapper build_path method marks routes where path parameters are part
of a path segment as custom routes by altering the regular expression, e.g:

    get '/foo-:bar', to: 'foo#bar'

There were some edge cases where certain constructs weren't being picked
up and this commit fixes those.

Fixes #23069.

Fix the API documentation layout of after_*_commit

Just noticed this on the [edge API].

[ci skip]

[edge API]: http://edgeapi.rubyonrails.org/classes/ActiveRecord/Transactions/ClassMethods.html