chore: update setup-ruby version in pr-test work flow

[NickBurkhartBB]

Describe your changes

update the setup-ruby action version to work with latest ubuntu runner and not have it get picked up as self hosted runner

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Test Plan

• verify test PR workflow after change

Checklist before requesting a review

• A self-review of my code has been completed
• Tests have been added / updated if required
• Documentation has been updated to reflect these changes