ci: add unit test workflow for pull requests

[teo-nikolov]

Proposed changes

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Types of changes

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• Bugfix (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)
• Documentation Update (if none of the other choices apply)

Checklist

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• I have read the Contributing Guide
• I have signed the CLA
• Lint passes locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added the necessary documentation (if appropriate)
• Any dependent changes have been merged and published in downstream modules

Further comments

If this is a relatively large or complex change, kick off the discussion by explaining why you chose the solution you did and what alternatives you considered, etc...

[github-actions]

🎉 This PR is included in version 1.3.1 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

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