Fix have_enqueued_mail with global id arguments

This reverts commit 6eb04594.

Improve mailer argument deserialisation for 6.1 on Ruby 3.1

Upgrade FFI now its safe to do so

Add additional logic to the ActionMailer argument parsing to accomodate for differences under Ruby 3.1/Rails 6.1

Co-authored-by: Fabio Napoleoni <f.napoleoni@gmail.com>
Co-authored-by: Phil Pirozhkov <hello@fili.pp.ru>

Exclude both the "bundle" and "tmp" directory.  The former ensures we don't run rubocop against installed gems.  The latter ensures we don't run it against generated code and apps locally.

https://github.com/rubygems/bundler/pull/6728

ailure/Error: expect(`bundle exec #{script} 2>&1`).to be_empty
       expected `"Your RubyGems version (2.7.6.3)) has a bug that prevents `required_ruby_version` from working for Bundler. Any scripts that use `gem install bundler` will break as soon as Bundler drops support for your Ruby version. Please upgrade RubyGems to avoid future breakage and silence this warning by running `gem update --system 3.2.3`\n".empty?` to be truthy, got false

https://www.ruby-lang.org/en/news/2021/12/25/ruby-3-1-0-released/
https://rubyonrails.org/2021/12/15/Rails-7-fulfilling-a-vision

Fix scaffold template with namespace and `--model-name` option

Fix broken table in YARD doc

Remove extra blank in README.md.

Previously it was "successfully subscribes" which has very little to do with this particular test. Probably it's an artifact from copying the more general action cable tests somewhere. I found this because it shows up on documentation when googling the have_broascasted_for matcher. The message I chose is consistent with the others in this file: all existing similar tests have this message.

Some of them are off, and should better be referenced by a ref.
GitHub performs a redirect from master to main.

I'm not aware of the magic how `bundle install` worked when we pointed
to `rails`' `master` branch. `git fetch origin master` in Rails source
fails.

related:
https://github.com/rspec/rspec-rails/issues/2532

change ns_file_name to singular_table_name to support --model-name option.

related:
https://github.com/rspec/rspec-rails/issues/2532

- check if parameter name is not admin_post
- check if test contains Post.create instead of Admin::Post.create

related:
https://github.com/rspec/rspec-rails/pull/2534#issuecomment-973887145

Replace ns_file_name to singular_table_name.
https://github.com/rspec/rspec-rails/issues/2532

    [!] There was an error parsing `Gemfile`:
    [!] There was an error parsing `Gemfile-rails-dependencies`: You cannot specify the same gem twice with different version requirements.
    You specified: sprockets-rails (>= 2.0.0) and sprockets-rails (>= 0). Bundler cannot continue.

     #  from /home/runner/work/rspec-rails/rspec-rails/Gemfile-rails-dependencies:10
     #  -------------------------------------------
     #    gem 'sprockets', :git => 'https://github.com/rails/sprockets.git', :branch => 'master'
     >    gem 'sprockets-rails', :git => 'https://github.com/rails/sprockets-rails.git', :branch => 'master'

Prefer require_relative to avoid calculating relative paths