Contributor project automations via workflows

[sam20908]

Fixes #960

This PR adds automation for contributors to move their PR between "Work In Progress" and "Initial Review".

Previous attempt by #829 was very close, but it needed pull_request_target to allow fork PRs to access secrets. This technically builds upon that (even I didn't know there was a previous attempt when I implemented this).

Automation So Far

• /pr wip moves the PR card to "Work In Progress". It only searches through "Initial Review" and "Final Review" for now (because the assumption right now is that PRs that got through those reviews are ready to go), can change if requested.
• /pr review moves the PR card to "Initial Review", it only searches through "Work In Progress" for the PR card.

Other Automation Ideas

• Automatically adds PR as a card to "Initial Review" in "Code Reviews" project when the PR is submitted
• Drafted PRs automatically puts the PR into "work in progress" status, same effect as /pr wip

Design Comments

• No idea if a secret is really needed for STL (at least I didn't, tested with a separate account to fork the experimental repository and created a PR).
• Moving the card requires JavaScript as there is no capable Actions to handle the way its being triggered, although there is https://github.com/alex-page/github-project-automation-plus, but it requires getting triggered through issues, and another workflow adding label wouldn't trigger it by default.
• There was no API to get the project and card the PR is assigned to, so majority of moving card code was to find out where the corresponding card is related through API calls.

Experimentation repository can be found here: https://github.com/sam20908/STL-PR-Workflow

[sam20908]

Some of the JavaScript questions so far.

[sam20908]

New places of FIXME's.

[StephanTLavavej]

While the Code Reviews project has a Work In Progress column, we deleted the "work in progress" label a few months ago as it seemed to be redundant. We can re-add it at any time, though.

[sam20908]

Sure, I'll just remove the automation to add/remove the label for now.

[sam20908]

This is officially ready for review, with everything addressed and the description updated.

[sam20908]

One comment about the additional complexity to add logging for moving from 'Initial Review' or 'Final Review' column to 'Work in Progress' column.

[strega-nil-ms]

There're some clean ups possible

[StephanTLavavej]

Thanks! I'll validate and push changes, one moment...

[StephanTLavavej]

I pushed a conflict-free merge with main, followed by minor typo fixes, semicolons, and adjusting the conditions to be short-circuit friendly, validating that the commenter is the same user as the PR author, and changing the commands to be easier to remember. I was unable to fully validate this in my repo since I don't have a classic project and can't make one anymore, but @CaseyCarter was able to help me validate the same-user check which is the part I was worried about (also this validated the YAML line wrapping I used; > drops newlines in the middle but keeps one at the end).

Note that the if condition is a GitHub expression, so it uses a double equal, not the triple equal that's desirable in JS.

In the future, it may be desirable to fuse these two actions into one YAML file. Also, if we migrate to GitHub's modern projects, this code will need to change (no plans at the moment though).

[StephanTLavavej]

I'm mirroring this to the MSVC-internal repo - please notify me if any further changes are pushed.

[StephanTLavavej]

Thank you for this major workflow improvement - this will be incredibly useful for contributors! 😻 💯 🥇