Update docker workflow

[PGijsbers]

This PR updates the docker workflow:

• The workflow can now also publish images to docker hub under aiod/metadata_catalogue. This happens when:
  • A release is made, pushes with tags latest and whatever the version tag is e.g., v1.3.20240308.
  • Develop is pushed, pushes with tag develop
  • The workflow is dispatched through the Actions tab on Github, pushes with the tag provided in the input
• The workflow can update the description of that repository, based on the content of docker-description.md
• Using the workflow dispatch, can also update the repository description(s) without updating any image.

A build cache is used to avoid double work between build and push jobs, but it seems to persist between workflows so this hopefully also speeds up the workflow. Otherwise, I would expect a slight slowdown as splitting the workflow into separate jobs (which run on separate runners), means we have to import/export the image from build to test.

I had hoped to be able to push the built image from build directly without rerunning build. While it uses cache now, and thus shouldn't take too much extra time, this largely negates the benefit of splitting build and test. I would consider merging those jobs again as it should result in a speed up, though it 'feels' nice that the jobs are now separate.

[!warning] Before merging, I still want to verify that the develop and release triggers and flow are set up appropriately. I will do this on a fork. But I don't suspect any (major) changes.

[PGijsbers]

I am fairly confident the workflow works as intended, as evidence:

• https://github.com/PGijsbers/AIOD-rest-api/pull/1 does not trigger the docker workflow
• https://github.com/PGijsbers/AIOD-rest-api/pull/2 does trigger the docker workflow, but only executes build and test
• A push to develop does run the workflow and determines a :develop tag (the workflow fails to authenticate because I did not configure credentials in my fork).
• A release does run the workflow and determines a :v* and :latest tag (the workflow fails to authenticate because I did not configure credentials in my fork). Note that this is problematic if we ever were do releases for versions which are not most recent (e.g., bugfix patch on an old release). I don't think this will really come up, and even if so we can trigger the action also from the Actions tag to re-release the :latest image.

• A workflow dispatch can be used to run the workflow with the provided tag (in this case :workflow-dispatch).

  I noticed in the process one time the docker tests failing due to the backup test. I am not sure exactly how that happened. In this case however I did find that it is actually really nice that we split build and test, since I can re-run just the test job independently.

  So I think this is good to merge (but please let me know if the open thread is resolved).