CLA Assistant - Automate commiters license agreement

[zonkmachine]

Enhancement Summary

Automating Contributor License Agreement. When submitting a PR we can let an application/GitHub Action ask for license compliance.

I came across this when submitting a simple change to the KiCAD repository. Quick and simple, a very nice experience.

https://github.com/cla-assistant/cla-assistant or the GitHub Action, https://github.com/cla-assistant/github-action

[Rossmaxx]

A similar CLA exists with microsoft's vcpkg C++ package manager. Might as well be good to have.

[Rossmaxx]

But to add, someone in the organisation with the perms should do it.