Adds YAPF to requirements and as a CI step

[dtasev]

Summary of work

Adds YAPF to requirements and as a CI step

How to test your work

Tests should pass

Fixes #915

[keiranjprice101]

Possibly wishful thinking, but is it possible to add an action that will run yapf and commit the output ?

edit: it appears something like this is possible https://github.com/diegovalenzuelaiturra/yapf-action

[dtasev]

I don't mind that tbh - do you think it might be annoying if you decide to add more changes but then you can't push & have to rebase/merge the formatting changes?

[keiranjprice101]

You can just pull the formatting change and continue from there no?

[dtasev]

Yeah but if you don't notice and continue working after pushing, then at some point you might get a lot of conflicts. Perhaps some bot would be better, i.e. if you comment @Format or something it just does it and commits?

[keiranjprice101]

That could be nice, especially if we can combine it with a branch protection rule that wont allow merging until the @Format has been triggered (Or whatever the manual trigger event is)

[rickybassom]

You can have a look at this code I used to trigger code scanning by commenting on a PR. In the end I decided to go for a workflow_dispatch event that can be triggered from Actions > Code Scanning > Run Workflow.

I suppose both methods would work for triggering a YAPF action.

[dtasev]

Hmm I did some looking around and https://unibeautify.com/ looks like exactly what we were discussing above. I will try to integrate it in to this repo.

[dtasev]

Unibeautify should provide that ability to merge the formatted changes, however it doesn't seem to be working right now and I'm trying to get some help from the CI maintainers at Unibeautify/ci-issues#5

In the meantime I've added back the YAPF CI job and I don't think this should hold up this PR