Fixes #21450 - Update rubocop to 0.51.0

Fixes #18618 - Use Dynflow as an ActiveJob backend

This commit initializes the Dynflow world in a very similar manner to
foreman-tasks (if a Dynflow world is available from foreman-tasks, we
use that one).

fixes #15751 - replace spork with spring in development

To make use of it, run bin/rails and bin/rake rather than plain
rails or rake commands, and run `spring status` or `spring stop` to
check and stop current background processes.

Test log removal has moved to the logging framework as the file would...

Refs #3809 - Turning on some rubocop cops

fixes #12892 - moves rails binaries to Rails.root/bin

this is simply the output of ```rake rails:update:bin```
and deletion of old script/rails.