Prepare for 4.4.2

Merge pull request #750 from rails/rmf-release

Add release workflow

Merge pull request #749 from Shopify/hm-ovztstypytzzqmqr

Fix spawn_on_env vars leaking from server to app

Prepare for 4.4.1

Merge pull request #744 from rails/pc-signal-exit-code

Test signal exit code scenario.

Expect exit status code in spring client

Pass signaled exit code properly to the client

Merge pull request #747 from rails/rm-ruby-4

Add summary job to CI workflow

Fix issue with bundler 4

Lock minitest to < 6

Test with Rails 8.1 and Ruby 4.0