feat: added much needed integration testing using containers

[gerblesh]

This PR does a couple things at the moment:

• Sunset the old makefile in favor of using just and handle integration testing
• Move away from the Makefile to use just (we are not using C, justfiles are much more well suited as a task runner)
• add a new option (--dry-run) to the ublue-update CLI to allow running updates as a "dry-run" for testing on the container
• Renovate the release-please action to actually function
• Fix brew updates (custom brew update driver)