Move Product Intelligence Dangerfile logic to helper module

What does this MR do and why?

Related to #347246 (closed)

This MR moves the product intelligence Dangerfile logic into its counterpart ruby module. We do it because that makes the code testable. This MR also adds tests covering the logic that was previously handled in Dangerfile and makes module's methods private.

Screenshots or screen recordings

These are strongly recommended to assist reviewers and reduce the time to merge your change.

How to set up and validate locally

1. Create an MR for the GitLab repo
2. Push changes that modify any of the files that require product intelligence review.
3. Check if the danger bot generates a proper report for the product intelligence section and/or adds needed labels.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.