Fixes 1378 - Add Ruby 3.1 and Rails 7.0 to the CI matrix

[petergoldstein]

This PR adds Ruby 3.1 and Rails 7.0 to the CI matrix. In addition to the change to the basic GitHub Actions YAML, the following changes were required:

1. In test/test_helper.rb restrict setting config.active_record.sqlite3.represent_boolean_as_integer to Rails version 5.2.x
2. In test/unit/resource/resource_test.rb there's no guarantee on the ordering of classes returned by subclasses, so loosen the spec to pass if the correct subclasses are returned in any order.
3. Updated the CI configuration to pull the latest patch version for each minor version of Ruby and Rails.

All Submissions:

• I've checked to ensure there aren't other open Pull Requests for the same update/change.
• I've submitted a ticket for my issue if one did not already exist.
• My submission passes all tests. (Please run the full test suite locally to cut down on noise from travis failures.)
• I've used Github auto-closing keywords in the commit message or the description.
• I've added/updated tests for this change.

Test Plan:

Reviewer Checklist:

• Maintains compliance with JSON:API
• Adequate test coverage exists to prevent regressions

[bf4]

@lgebhardt @dgeb need help going through these?

[petergoldstein]

I've updated this to the include Ruby 3.2 and the latest Rails patch versions.

@lgebhardt or @dgeb is anything else required for this PR? Is this gem being maintained at this point?

[bf4]

@petergoldstein Merged! Thanks for your contribution.