Enabling Github Action for forked pull requests

[bplociennik]

Would be great to automatically run one of the basic Github Action called Lint and test for every pull request (even if it comes from a forked repository).

https://docs.github.com/en/actions/managing-workflow-runs/approving-workflow-runs-from-public-forks
https://github.blog/2020-08-03-github-actions-improvements-for-fork-and-pull-request-workflows/

name: 'Lint and test'

on:
  push:

Currently, it works only on pushed to this repository direct on one of the branches.

TODO:
our repo github actions triggered by forks should have access to secrets to be able to run our tests