Revert "Improve consistency with official controller spec style"

Improve consistency with official controller spec style

Improve implicit description for RSpec::Rails::Matchers::ActionCable::HaveBroadcastedTo

Previously, tests defined like this:

```rb
it do
  expect { some_action }.to have_broadcasted_to("stream_name").from_channel(SomeChannel).with("some_data")
end
```

would implicitly be given the description `have broadcasted to`, which is derived from the name of the matcher method.
This didn't carry any extra information about the data we're expecting to be broadcast from the channel - behaviour
which would be very welcome in combination with Turbo Streams. With a matcher for Turbo Streams, we might benefit from
a description like "broadcast exactly 1 messages to stream with turbo-stream[action="append"][target="some_list"]".

Co-authored-by: Jon Rowe <hello@jonrowe.co.uk>
Co-authored-by: Phil Pirozhkov <pirj@users.noreply.github.com>

Update method name in HaveEnqueuedMail (job_match? to job_matches?)

Fix rails main for solid cache

This change fixes a bug wherein a spec that expects no mail to have been
enqueued will fail (falsely claiming that a mail _was_ enqueued) if any
_non-mail_ job is enqueued, even if indeed no _mail_ job is actually
enqueued.

This bug was introduced in ab6e6e83 / #2780 , which was first included
in the 7.0.0 release.

In that change, the `RSpec::Rails::Matchers::ActiveJob::Base`
`job_match?` instance method was renamed to `job_matches?`. The problem
is that `RSpec::Rails::Matchers::HaveEnqueuedMail`, which inherits from
`RSpec::Rails::Matchers::ActiveJob::Base` (via
`RSpec::Rails::Matchers::ActiveJob::HaveEnqueuedJob`), intends to
override that method, which it does by defining its own `job_match?`
instance method. However, because this `job_match?` method name is no
longer the same as the (now so called) `job_matches?` method that it
intends to override, the `job_match?` method of
`RSpec::Rails::Matchers::HaveEnqueuedMail` is no longer having the
intended override effect on the behavior of the matcher, producing the
aforementioned bug.

This change resolves the issue by updating the method name in the
`RSpec::Rails::Matchers::HaveEnqueuedMail` subclass from `job_match?` to
`job_matches?`, reflecting that renaming that was done in the parent
class in ab6e6e83 .

Silence warning in mailer preview path check

Fix Changelog.md typo.

Cleanup for versions 7

Drop support for rails versions < 7 in scaffold generator

Register Rails::CodeStatistics directory with test_directory arg

There is no need to edit the TEST_TYPES constant directly.

Prepare changes for 7.0.0