adding cpu only test Github job

[dkazanc]

• Removes (backs up) IRIS test
• Adds Github Actions to run CPU tests only
• Some tests do require CuPy and can be run with --cupy flag added. We will be running those as a part of the Jenkins job.

Checklist

• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I have made corresponding changes to the documentation
• I have added the user-release-note label in order to include this PR in the "Notable
  Changes for Users" section in release notes