document the return of `db:test:prepare`. Closes #18136. [ci skip]

This is a doc follow-up to #17739.

/cc @zzak
s/are edited and rerun/required modifications [ci skip]
Remove this line since we are using Rake to run our tests [ci skip]
I'm sorry but I would rather not link to a 7 year old blog post [ci skip]
Add subheadings for these sections [ci skip]
Use serve_static_files in guides [skip ci]
Use serve_static_files in guides, take 2 [skip ci]
Remove this section, it adds no real value [ci skip]
Merge branch 'master' of github.com:rails/rails
Correctly handle limit on int4 and int8 types in PG

PG doesn't register it's types using the `int(4)` format that others do.
As such, if we alias `int8` to the other integer types, the range
information is lost. This is fixed by simply registering it separately.

The other option (which I specifically chose to avoid) is to pass the
information of the original type that was being aliased as an argument.
I'd rather avoid that, since an alias should truly be treated the same.
If we need different behavior for a different type, we should explicitly
register it with that, and not have a conditional based on aliasing.

Fixes #18144

[Sean Griffin & ysbaddaden]
Add `force: true` to table created in tests

If the test is interrupted in a way that the teardown block fails to
run, the tests will fail to run until the table is removed manually
without this option.