[Feature]: Implement an HTCondor CI Workflow

### User Story

As a contributor for the HTCondor module,
I want to trigger the HTCondor CI pipelines,
So that my changes are properly tested and no regressions are injected into this package.

### Feature Description

As part of the separation of the python modules that interact with different grid gateways/compute elements, it is important to have automated tests that can validate changes made to the HTCondor python module, ensuring that changes are functional and that no regressions are added.

Given that we still don't have in this repository a python module to interact with HTCondor, I would suggest to provide the following deliverables in this ticket:
* a GitHub workflow that runs an HTCondor docker container, with the relevant daemons (master, collector, negotiator, schedd and startd)
* submit a condor job to this HTCondor container, using condor binary commands.
* track the job submitted
* verify the output files of the job to ensure that it went well

### Definition of Done

- [ ] The HTCondor CI pipeline is triggered
- [ ] Job submission works
- [ ] Evaluation of results/files is performed
- [ ] Harmonized onto the scaffold: `stacks/htcondor/` layout, `stacks.yml` entry, healthcheck,
creds in the shared volume, bespoke workflow removed

### Alternatives Considered

_No response_

### Related Issues

_No response_

### Additional Context

_No response_