Subprocess process manager for CI workflows

[PawelPlesniak]

Description

Fixes # (issue_number)

The objective is to run processes as subprocesses instead of SSH. The objective is to be able to run MSQT as a CI workflow, using SSH is blocked

Type of change

• Documentation (non-breaking change that adds or improves the documentation)
• New feature (non-breaking change which adds functionality)
• Optimization (non-breaking, back-end change that speeds up the code)
• Bug fix (non-breaking change which fixes an issue)
• Breaking change (whatever its nature)

Key checklist

• All tests pass (eg. python -m pytest)
• Pre-commit hooks run successfully (eg. pre-commit run --all-files)

Further checks

• Code is commented, particularly in hard-to-understand areas
• Tests added or an issue has been opened to tackle that in the future.
  (Indicate issue here: # (issue))

[PawelPlesniak]

At the moment, the processes grafeully exit (aside from gunicorn as usual). This needs some tweaks but is coming together nicely