github-actions-labeler: initial commit

[mofosyne]

This is an attempt at solving this idea #7174 of using https://github.com/actions/labeler to help assist in auto labeling PR based on file edited content.

Was hoping for PR complexity automation, but this particular github action doesn't appear to have enough flexibility for such logic. But this should help if it works.

I don't have a way to test this, so maybe have a quick lookover and it if makes sense and we can risk it, let's give it a shot.

---

Also made an issue ticket directly to the team at labeler to see if there is a possibility of having enumerated labels so we can better add auto complexity marking. actions/labeler#781

[mofosyne]

Btw on a side note... would it make sense to add paths-ignore to github actions to skip any markdown or doc only changes? How often do we only do documentation changes to this repo? If it's common enough, then it may be worth it.
(But I suspect this may be premature optimization to worry about this)

name: CI

on:
  pull_request:
    types: [opened, reopened, synchronize]
    paths-ignore:
      - '**/*.md' # Ignore markdown files
      - 'docs/**' # Ignore changes in the docs folder

https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#onpushpull_requestpull_request_targetpathspaths-ignore

[ggerganov]

I think the complexity labels are not really useful because they are subjective. We can keep them for now, but I wouldn't mind if we proceed without them

[ggerganov]

Btw on a side note... would it make sense to add paths-ignore to github actions to skip any markdown or doc only changes? How often do we only do documentation changes to this repo?

We already seem to skip most of the CI for doc-only changes:

9c4fdcb