Create a WMAgent/WMCore-dev image to run unittests

[d-ylee]

Impact of the new feature Create a development image of WMAgent/WMCore that includes unittests and necessary dependencies to run unittests

Is your feature request related to a problem? Please describe. While working on #11568 , if we want to run unittests in containers, we cannot use the production WMAgent image, since it does not contain unittests.

Describe the solution you'd like

• Creating a new development image dedicated for WMCore/WMAgent unittests that includes necessary dependencies to run unittests.
• Revisit current setup in cmsdocks and other locations and see if we can deprecate/remove older images.
• Update documentation

Describe alternatives you've considered

• Similar to the current image for unittests, running all 3 services together: CouchDB + MariaDB + WMAgent

Additional context Spec from cmsdist for creating a unittest docker image: https://github.com/cms-sw/cmsdist/blob/comp_gcc630/wmcorepy3-devtools.spec

services that we build and upload to PyPi: https://github.com/dmwm/WMCore/blob/master/.github/workflows/pypi_build_and_images.yaml#L29C17-L30C117

and list of services that we build a docker image https://github.com/dmwm/WMCore/blob/master/.github/workflows/pypi_build_and_images.yaml#L44

Repository that we build WMCore unit test image (and other images): https://gitlab.cern.ch/CMSDOCKS/dmwm/-/tree/master?ref_type=heads

[d-ylee]

I have been using a new Alma9 based image to run tests for WMCore. It can be found here: https://github.com/d-ylee/jenkins-test/tree/main/docker/wmcore-dev

[amaltaro]

@d-ylee I don't know if it helps in any shape or form, but yesterday I noticed that the test Alma9 image for MSUnmerged was using AlmaLinux directly instead of Cern Alma9 (I am sure there are some extra packages for the base image, even though I didn't check those).

Based on that, I created a new image to perform other tests and it's available in this commit (it brings in : https://github.com/dmwm/CMSKubernetes/pull/1452/commits/3e32e13ec7c1aa3d01de8e32a9252b9738f6af3d