Fix Rails 8.1 router keyword args deprecation warning

[mathieujobin]

@copilot Can you reopen #962 as your own. you can use the branch named ruby8-copilot which is already set to 9283da9 by James Dean Shepherd.

Please check rubocop, why it fails. might need to update rubocop gems and run it with rubocop --regenerate-todo --no-auto-gen-timestamp --exclude-limit 250

remove conditions around Rails 5.x and 6.x.
Update constraint to support only ruby >= 3.1 and rails >= 7.0,
update Changelog and bump to next minor version.

Thank you