Incremental sync for workflow_runs stream in GitHub source

[tovbinm]

Description

Since the community GitHub source now supports incremental sync for workflow_runs stream we should do that by default.

Type of change

• New feature (non-breaking change which adds functionality)

Checklist

(Delete what does not apply)

• Have you checked to there aren't other open Pull Requests for the same update/change?
• Have you lint your code locally before submission?
• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your core changes, as applicable?
• Have you successfully run tests with your changes locally?