fluentui feat(tools): introduce generic generator for various repo checks

Story 🧚‍♀️

Currently we don't have a common way how to write various local/CI checks, so we don't put repo into invalid state by accident.

Idea is to create pluggable solution with tests that we have confidence that things work.

The solution will be implemented as a pluggable nx generator

nx workspace-generator validate-repo --codeowners --pr-size=30 --workspace

where:

validate-repo name of generator
pluggable behaviour via flags (NOTE: contrived flags)
- --codeowners boolean flag that will run codeowners setup check
- --pr-size=30 configurable flag that will run PR size check and will break CI if user changed more than 30 files

[ ] init generator
[ ] implement codeowners check ( so we mitigate accidental removals of our automated Codeowner addition functionality )
- https://github.com/microsoft/fluentui/pull/22308/commits/b6fd07f32dc267f710db63334c12babcb5d78887#diff-3d36a1bf06148bc6ba1ce2ed3d19de32ea708d955fed212c0d27c536f0bd4da7L153
[ ] enable on CI

Apr 05 '22 16:04 Hotell

Because this issue has not had activity for over 180 days, we're automatically closing it for house-keeping purposes.