Gather pull request analytics

[aexvir]

As this was one of the main motivations for this project, we definitely need to focus on this :D

The metrics we'll be gathering initially will be

• [ ] Time the merge request has been on review (1)
• [ ] Pull request author
• [ ] Pull request reviewers / approvers
• [ ] Merge request intention (2)
• [ ] Merge request areas (3)
• [ ] Amount of LoC changes (added and removed)
• [ ] Amount of comments
• [ ] Amount of commits

1) The review time might be tricky to calculate, so we'll need to make some assumptions. I'm proposing the following:

GitHub: The review time will be calculated since the first reviewer has been added until the last reviewer has agreed or the PR has been merged. Draft MRs will be considered unreviewed even if there is a reviewer set (by some automation for example).

GitLab: The review time will be calculated since the first approver has been added until the MR is approved. WIP MRs will also be considered unreviewed even if there is a reviewer set.

2) The intention will be determined by checking the conventional commits commit types. We'll use some heuristics to determine it. I'm proposing the following:

Type	Commits
Maintenance	build | ci | chore | style | test
Bug fix	fix + ((maintenance) | docs)
Feature	feat + ((maintenance) | docs)
Improvement?	refactor | perf + (maintenance)
Documentation	docs

3) Gathered from conventional commits, that's it, no fancy stuff

[aexvir]

Of course everything is up for discussion 🙂