Add Ruby 3.1 to CI (#986)
Add Ruby 3.1 to CI (#986)

This PR adds Ruby 3.1 to CI.

It also cleans up an unnecessary exclusion for Ruby 3.0 / Rails 5.2 (Rails 5.2 was already removed from the CI matrix).

Co-authored-by: Philip Arndt <46f1a0bd5592a2f9244ca321b129902a06b53e03@p.arndt.io>
norman/friendly_id