[ci skip] actionview typo fixes.

This covers what #34626 fixes.

Reduce unused allocations when casting UUIDs for Postgres

Deprecate ActionView::PathSet as argument to ActionView::Base.new

Using the subscript method `#[]` on a string has several overloads and
rather complex implementation. One of the overloads is the capability to
accept a regular expression and then run a match, then return the
receiver (if it matched) or one of the groups from the MatchData.

The function of the `UUID#cast` method is to cast a UUID to a type and
format acceptable by postgres. Naturally UUIDs are supposed to be
string and of a certain format, but it had been determined that it was
not ideal for the framework to send just any old string to Postgres and
allow the engine to complain when "foobar" or "" was sent, being
obviously of the wrong format for a valid UUID. Therefore this code was
written to facilitate the checking, and if it were not of the correct
format, a `nil` would be returned as is conventional in Rails.

Now, the subscript method will allocate one or more strings on a match
and return one of them, based on the index parameter. However, there
is no need for a new string, as a UUID of the correct format is already
such, and so long as the format was verified then the string supplied is
adequate for consumption by the database.

The subscript method also creates a MatchData object which will never be
used, and so must eventually be garbage collected.

Garbage collection indeed. This innocuous method tends to be called
quite a lot, for example if the primary key of a table is a uuid, then
this method will be called. If the foreign key of a relation is a UUID,
once again this method is called. If that foreign key is belonging to
a has_many relationship with dozens of objects, then again dozens of
UUIDs shall be cast to a dup of themselves, and spawn dozens of
MatchData objects, and so on.

So, for users that:
* Use UUIDs as primary keys
* Use Postgres
* Operate on collections of objects

This accomplishes a significant savings in total allocations, and may
save many garbage collections.

Currently, `ActionView::Base.new` will raise a `NotImplementedError` when given an instance of `ActionView::PathSet` on initialization. This commit prevents the raised error in favor of a deprecation warning.

[ci skip] Updated the documentation for bulk delete in activerecord

Replaced usage of where.delete/destroy_all with delete/destroy_by

Fix reset of the source association when through association is loaded

The special case happens when through association has a custom scope
that is applied to the source association when loading.
In this case, the soucre association would need to be reset after
main association is loaded. See tests.

The special case exists when a through association has

Merge pull request #35325 from abhaynikam/add-query-method-delegation-test-for-destory-by-and-delete-by

Added delegation tests for delete_by and destroy_by methods

Deprecate LookupContext#rendered_format

Let Zeitwerk integration unhook AS::Dependencies

We no longer depend on `rendered_format` side effects, so we can remove
this method now. 🎉

Return rendered template objects from renderers

This commit introduces "rendered template" and "rendered collection"
objects.  The template renderers can now return a more complex object
than just strings.  This allows the framework to get more information
about the templates that were rendered.  In this commit we use the
rendered template object to set the "rendered_format" on the lookup
context in the controller rather than all the way in the template renderer.
That means we don't need to check the "rendered_format" every time we
render a template, we just do it once after all templates have been
rendered.

This commit is to remove direct access to the "rendered_format"
attribute on the lookup context.  "rendered_format" is an implementation
detail that we shouldn't test directly.

Pass the template format to the digestor

Reset column info after making Topic tz-aware

Introduce delete_by and destroy_by methods to ActiveRecord::Relation

This reverts commit 6b69ae51, reversing
changes made to 84bd9ada.

Reason: We already use "happen" a lots for callbacks and validations.

https://github.com/rails/rails/pull/35324#issuecomment-465096483

[ci skip]

Update active_record_callbacks.md [ci skip]

Change 'happen' to a more technical term

Don't allow `where` with invalid value matches to nil values

In AttributeMethodsTest, we make the global Topic class time zone-aware
which changes instance date time attribute casting behaviour. We need to
reset column info after the test because future tests don't expect Topic
date time columns to be time zone-aware.

Actionpack typo fix

[ci skip]