Better handling for required workflows

[marcogario]

Return the workflow path from the run rather than trying to fetch the workflow information when the workflow information is missing or refers to a required workflow.

This fixes the error:

Error: As of January 2024, this feature is fully deprecated and creating required workflows is only available with repository rulesets. All existing workflows have been automatically migrated to rulesets. Learn more about rulesets: https://github.blog/2023-10-11-enforcing-code-reliability-by-requiring-workflows-with-github-repository-rules/

I've tested this by setting up a required workflow using the action version from this version and confirmed it works.

Note: We are reporting the path as if it exists in the current repo, but that is not the case. Logic that relies on making a distinction here might be affected.

Merge / deployment checklist

• [x] Confirm this change is backwards compatible with existing workflows.
• [x] Confirm the readme has been updated if necessary.
• [x] Confirm the changelog has been updated if necessary.