changed `rails/activestorage` to `rails/rails`.

Add Active Storage to Rails 

If an AWS bucket name includes a `.` (e.g. `bucket.name`), then the canonical
URL for an object will start with "https://s3.amazonaws.com/bucket.name/"
and not with "https://bucket.name.s3.amazonaws.com/".

The URL tests have now been separated into two separate asserts, to ensure
that both the "s3.amazonaws.com" and the "bucket.name" components are included,
but not specifically in that order.

Before we forget...

Do not let use `serialize` on native JSON/array column

The test was passing before because it was not being testes correctly.

Now we create a different engine that is loaded before the already
exising and we make sure that the first call for isolate_namespace is
what takes effect.

What we want to test is that two different calls to isolate_namespace
with the same module doesn't change the original railtie. We can do that
defining two different railties.

We can't call in the application because this method is not supposed to
be called in an Application class.

Use `assert_nil` if `value` is nil in `assert_field_default_value`

And deal with a temporary test fix until we allow you to skip active storage.

Use `Concurrent::Map` than `Mutex` and `Mutex_m` for statement caches

Remove extra empty line

Statement caches are used as a concurrent map. It will more clarify to
using `Concurrent::Map`.

Deprecate `LoadError::REGEXPS` constant

since 4ad1a52f, `LoadError::REGEXPS` is no longer needed.

We are already removing the braces around hash parameters in the last
argument in other places so we should not change the entire codebase
because of two places.

Change azure core dependency

Make Rubocop happy about ActiveStorage

Improve bundler binstub error message

Everything inside the app directory of a engine is autoload/eager loaded automatically so we don't need to require them.

It's worth considering whether we should hide these by default, but I'm kinda thinking no. It's very reasonable that someone would want to call these directly, so they should be documented.

FormHelper includes FormTagHelper so we don't need to define two methods

Also make sure file_field doesn't mutate the original options passed in.

When Active Storage is not loaded and direct_upload is used on
file_field_tag we should not raise an exception.

cc @rafaelfranca

I know those methods are unlikely to change but having one line method
is hard to read and also hard to modify.

Running `rubocop activestorage` before this commit resulted in 20 offenses.
This commit only fixes:

- Trailing whitespace detected
- Space inside } missing
- Put one space between the method name and the first argument.

The other offenses are left since they are intentional according to
@georgeclaghorn (https://github.com/rails/rails/pull/30061#issuecomment-319999190)

Passing `klass` to `StatementCache.new`

[ci skip]

Actually `StatementCache#execute` is always passed the same klass that
the owner klass of the connection when the statement cache is created.
So passing `klass` to `StatementCache.new` will make more DRY.