Previously `ActiveSupport::Duration.parse` used `Time.current` and
`Time#advance` to calculate the number of seconds in the duration
from an arbitrary collection of parts. However as `advance` tries to
be consistent across DST boundaries this meant that either the
duration was shorter or longer depending on the time of year.

This was fixed by using an absolute reference point in UTC which
isn't subject to DST transitions. An arbitrary date of Jan 1st, 2000
was chosen for no other reason that it seemed appropriate.

Additionally, duration parsing should now be marginally faster as we
are no longer creating instances of `ActiveSupport::TimeWithZone`
every time we parse a duration string.

Fixes #26941.

allow ActiveRecord::Core#slice to use array arg

Fix the order of `create_table` to match a comment about `:inverse_of…

Remove `Rack::Runtime from console log [ci skip]

remove warning from big integer test

Add missing space in Migrations guide [ci skip]

These comment sometimes explain a face which does not match
the face.

In ActiveRecord test :men, :faces, :interests and :zines tables are
used for `:inverse_of` test cases, not `:wheels`.

This removes the following warnings.

```
activemodel/test/cases/type/big_integer_test.rb:15: warning: ambiguous first argument; put parentheses or a space even after `-' operator
```

update doc about assets digest class [ci skip]

The default digest class changed to SHA256 in sprockets 3.0.
Ref: https://github.com/sstephenson/sprockets/pull/647

Support plain loggers in DebugExceptions

This reverts commit aaf561d2, reversing
changes made to 83776676.

Reason: It is not a good idea to connect to the database on generators

Fix for has_and_belongs_to_many & has_many_through associations

Dynamically show available sql types [ci skip]

I have been seeing people setting `Logger` instances for `config.logger`
and it blowing up on `rails/web-console` usage.

Now, I doubt many folks are manually setting `ActionView::Base.logger`,
but given that `DebugExceptions` is running in a pretty fragile
environment already, having it crash (and being silent) in those cases
can be pretty tricky to trace down.

I'm proposing we verify whether the `ActionView::Base.logger` supports
silencing before we try to do it, to save us the headache of tracing it
down.

They're just barren on the site and confure more than guide, instead
rely on the built in --help to guide users.

Remove unnecessary `respond_to?(:indexes)` checking

Follow up to 454460e8.

Rebuild the sentence so the bit about only symbols allowed comes less
out of left field and fits in better with the existing doc.

Also remove the `(Legacy syntax)` construct. The sections are properly
nested under `=== Options` with `====` and look fine on the generated
API doc site.

Add documentation for `config.assets.version`

I'm sorry for causing #24168. I wasn't aware of --no-helper and --no-assets.
So I'm adding them to the help message.
I'm still not sure how to show `--no-test-framework` though.

Fix :stopdoc: to :startdoc: [ci skip]

Fix HABTM associations join table resolver bug on constants and symbols

A query may wait on a database-level lock, which could lead to a
deadlock between threads.

Fixes an issue where time_zone_conversion that causes an exception in…

Following off of https://github.com/rails/rails/issues/15945, I realized that super
needs to be the first thing that is called in an AbstractModel's inherited method.
I was receiving errors within the inherited method of time_zone_conversion, so I tested
locally by moving super to the top of the method declaration. All exceptions went away.

Using Constant and symbol class_name option for associations are valid but raises exception on HABTM associations.
There was a test case which tries to cover symbol class_name usage but doesn't cover correctly. Fixed both symbol usage and constant usage as well.

These are all working as expected now;
```
  has_and_belongs_to_many :foos, class_name: 'Foo'
  has_and_belongs_to_many :foos, class_name: :Foo
  has_and_belongs_to_many :foos, class_name: Foo
```

Closes #23767

Use Regexp#match? rather than Regexp#===

Regexp#match? should be considered to be part of the Ruby core library. We are
emulating it for < 2.4, but not having to require the extension is part of the
illusion of the emulation.

remove unused `RedirectBackError` class

Follow up to 333bfd89

fix initializer name [ci skip]