Lazy checking whether or not values in IN clause are boundable

Make it easier to find abort documentation

Update ActiveStorage Attachment model documentation [ci skip]

Since #33844, eager loading/preloading with too many and/or too large
ids won't be broken by pre-checking whether the value is constructable
or not.

But the pre-checking caused the type to be evaluated at relation build
time instead of at the query execution time, that is breaking an
expectation for some apps.

I've made the pre-cheking lazy as much as possible, that is no longer
happend at relation build time.

Add observing emails to action mailer guide [ci skip]

What is important to tell is that the database configuration could not
be loaded.

Fixes #34296.

Remove `--skip-yarn` in favor of `--skip-javascript`

Merge pull request #34297 from albertoalmagro/full-remove-upgrade-information-from-assets-pipeline-guide

Fully remove duplicated upgrade information [ci skip]

On #34261 we removed the whole upgrade section. This warning is also
included in the Upgrade guides [here](https://github.com/rails/rails/blame/master/guides/source/upgrading_ruby_on_rails.md#L1390)
and should also be removed.

Fix typo of duplicated `the`

Hide PG::Connection from API docs [ci skip]

[ci skip] Fix PullRequest link on Rails 5.1 Release Notes

MySQL 8.0.13 raises `ER_NO_REFERENCED_ROW` and `ER_ROW_IS_REFERENCED`

when user has no parent table access privileges

Refer https://dev.mysql.com/doc/relnotes/mysql/8.0/en/news-8-0-13.html#mysqld-8-0-13-errors

>>
* Previously, the ER_NO_REFERENCED_ROW_2 and ER_ROW_IS_REFERENCED_2 error messages
for foreign key operations were displayed and revealed information about parent tables,
even when the user had no parent table access privileges. Error handling for this situation has been revised:

  * If the user does have table-level privileges for all parent tables,
    ER_NO_REFERENCED_ROW_2 and ER_ROW_IS_REFERENCED_2 are displayed, the same as before.

  * If the user does not have table-level privileges for all parent tables,
    more generic error messages are displayed instead (ER_NO_REFERENCED_ROW and ER_ROW_IS_REFERENCED).
<<

This pull request addresses these 3 failures:

```ruby
$ ARCONN=mysql2 bundle exec ruby -w -Itest test/cases/adapter_test.rb -n /foreign/
Using mysql2
Run options: -n /foreign/ --seed 14251

F

Failure:
ActiveRecord::AdapterForeignKeyTest#test_foreign_key_violations_are_translated_to_specific_exception_with_validate_false [test/cases/adapter_test.rb:348]:
[ActiveRecord::InvalidForeignKey] exception expected, not
Class: <ActiveRecord::StatementInvalid>
Message: <"Mysql2::Error: Cannot add or update a child row: a foreign key constraint fails: INSERT INTO `fk_test_has_fk` (`fk_id`) VALUES (1231231231)">

... snip ...

rails test test/cases/adapter_test.rb:343

F

Failure:
ActiveRecord::AdapterForeignKeyTest#test_foreign_key_violations_on_delete_are_translated_to_specific_exception [test/cases/adapter_test.rb:368]:
[ActiveRecord::InvalidForeignKey] exception expected, not
Class: <ActiveRecord::StatementInvalid>
Message: <"Mysql2::Error: Cannot delete or update a parent row: a foreign key constraint fails: DELETE FROM fk_test_has_pk WHERE pk_id = 1">

... snip ...

rails test test/cases/adapter_test.rb:365

F

Failure:
ActiveRecord::AdapterForeignKeyTest#test_foreign_key_violations_on_insert_are_translated_to_specific_exception [test/cases/adapter_test.rb:358]:
[ActiveRecord::InvalidForeignKey] exception expected, not
Class: <ActiveRecord::StatementInvalid>
Message: <"Mysql2::Error: Cannot add or update a child row: a foreign key constraint fails: INSERT INTO fk_test_has_fk (fk_id) VALUES (0)">

... snip ...

rails test test/cases/adapter_test.rb:357

Finished in 0.087370s, 34.3366 runs/s, 34.3366 assertions/s.
3 runs, 3 assertions, 3 failures, 0 errors, 0 skips
$
```

Fix CSP dynamic sources

Remove mentions about `javascripts` option from the guide about generators [ci skip]

Add docs to ActiveSupport::Notifications.subscribe

Remove "Upgrading from Old Versions" from Asset Pipeline Guide [skip ci]

Add missing dot in comment in .gitignore template

[ci skip]

This option is unused since #33079.

Follow up #34277

Related to #33079

Unify changelog entries related to `database` option of Rails generators [ci skip]

My submission for the tiniest commit and PR contest: add a missing dot in a comment line in the generator template for .gitignore.
(I just noticed this missing; consistency is king :-)

Fix #33914 : Remove dependent: :destroy option from the belong_to example since there is a warning associated with the usage of dependent: :destroy along with belongs_to 

This commit removes the dependent: :destroy option from the belong_to example since there is a warning associated with the usage of dependent: :destroy along with belongs_to. Based on the feedback on the issue #33914, I  replaced dependent: :destroy with touch: :books_updated_at which will make the example consistent with the example that already exists on that page.
 * Also Removing the touch option from the belong_to scopes example as the option doesnt have any relation to association scope.

Clarify i18n load paths gotcha

There is no controller instance when using a redirect route or a
mounted rack application so pass the request object as the context
when resolving dynamic CSP sources in this scenario.

Fixes #34200.

Previously if a dynamic source returned a symbol such as :self it
would be converted to a string implicity, e.g:

  policy.default_src -> { :self }

would generate the header:

  Content-Security-Policy: default-src self

and now it generates:

  Content-Security-Policy: default-src 'self'

Clarify `I18n.load_paths` vs `Rails.application.config.i18n.load_paths`
behaviour.

[Gannon McGibbon + Alberto Almagro Sotelo]

Since #33079 Webpacker the default JavaScript compiler for Rails.
Webpacker uses `yarn` so seems like it doesn't make sense for Rails to keep
`--skip-yarn` option.

Remove extra call `remove_file` on `rails new` with `--skip_action_cable`

Rename event variable

Remove yarn's files from `.gitignore` template

There is no need to remove this file since the line below
removes entire directory in which that file is placed.

Merge pull request #34277 from bogdanvlviv/remove-javascripts-javascripts_engine-options-for-generators

Remove `javascripts` and `javascript_engine` options for generators