`Computer` class needs to be require

See #17217 for more details

[ci skip] Remove deprecated testing tasks

This has changed recently and so rake test:all and rake
test:all:db are deprecated.

also increase the version of pg required so that people will get the
GVL friendly version

[ci skip] Improve upon testing tasks guide

Add missing testing tasks and also improve upon tasks descriptions

[ci skip] Capybara added to other testing approaches

name keywords

Abstract encoding strategy for ActiveSupport::MessageVerifier

Fix Rails::Paths::Path.unshift interface

Follow the coding conventions

simplify rake test vs rake test:all

[ci skip] Use American English and replace "behaviour" with "behavior".

Update to consistently use American English [ci skip]

Time includes DateAndTime::Zones acts_like(:time)

add a Table#name accessor like TableDefinition#name

Closes #17586

Renames `rake test:all` to `rake test` by changing old `rake test:run` to previous version of `rake test:all`.  Removes old definition of `rake test`. Also renames `rake test:all:db` to `rake test:db` and deprecates `rake test:all` & `rake test:all:db`

Replaces the following in two places:

```diff
-require ::File.expand_path('../config/environment',  __FILE__)
+require ::File.expand_path('../config/environment', __FILE__)
```

Just prefer secrets over config

Allow fallback to LegacyKeyGenerator when secret_key_base is not set but secrets.secret_token is

remove never called method `limited_update_conditions`

Tiny improvement in sqlite3 adapter

  - remove unused method `supports_add_column?`
  - change additional restriction method to `valid_alter_table_type?`
  - fix code style

Fix bug found when running individual tests against #17217 after merging

Fix that a collection proxy could be cached before the save of the owner, resulting in an invalid proxy lacking the owner’s id

Conflicts:
	activerecord/CHANGELOG.md

We added a deprecation warning for these cases in aa1fadd4, so these are now
causing deprecation warnings in the test output. AFAICT, in these two cases, the
option is not integral to the purpose of the test, so they can be safely removed