Expand test matrix to more recent versions of Ruby

[pcothenet]

What

• Add 3.4 and 3.3

Why

• Find issues with dependencies

SDK Release Checklist

• Have you added an integration test for the changes?
• Have you built the gem locally and made queries against it successfully?
• Did you update the changelog?
• Did you bump the package version in the code generator?
• If endpoints were removed, did you manually remove the corresponding files? (this should be rare)
• For breaking changes, did you plan for the release of the new SDK versions and deploy the API to production?