chore: add github action to run test suit

[bluebrown]

I have added a GitHub action to run the tests. This can be used to protect the main and releases branches on pull requests.

Due to the way GitHub actions work, you may need to do some "hacks" to have that pipeline run 1 time, before it is selectable via branch protection.
The way I did that was settings the on condition to push (and nothing else). I guess one could make a dummy branch and push to that just to get it working.
Once that ran one time, the actual on conditions can be specified. For example, using the ones in this PR.

on:
  push: 

There is probably a better way.

[bluebrown]

Here is an example of branch protection integration on my fork. I have used a dummy main branch to make the pr against, and enabled branch protection for that branch. bluebrown#3