Get the automated release to pypi working

[DavidPCoster]

According to pypi, EasyVVUQ was last updated (to 1.2) on March 28, 2023. It seems as the two releases by @djgroen did not go through, though the March 2023 by @wedeling did.

Compare https://github.com/UCL-CCS/EasyVVUQ/releases and https://pypi.org/project/easyvvuq/#history

We need to understand what is going wrong, find a fix, and document the release procedure.

[ZedThree]

The error in your publish workflow is:

ERROR    HTTPError: 403 Forbidden from https://upload.pypi.org/legacy/          
         Invalid or non-existent authentication information. See                
         https://pypi.org/help/#invalid-auth for more information.   

Could be as simple as your API token has expired. I recommend moving to the Trusted Publisher workflow. It's very easy to set up, only takes a couple of minutes, and is the most secure option

[DavidPCoster]

Following the instructions in pip_packaging_instructions.txt, I was able to perform the release for v1.3 from my laptop with tag v1.3 checked out.

We have the manual procedure working, but the automated release via github is still not working.