[Bug]: Python-based hooks do not work on older distributions

[NucciTheBoss]

After upgrading the snap to core24 to so that we could pull the librocm-smi-dev package from Ubuntu Archive rather than a custom PPA I built, it seems that the Python-based hooks are no longer working on older distributions such as Focal or Jammy. It fails with a common error that typically indicates that your python virtualenv is corrupted. Error output below:

On 24.04 (Noble)

$ snap install slurm --classic --channel latest/candidate
2024-06-11T12:20:31Z INFO Waiting for automatic snapd restart...
slurm (candidate) 23.11.1 from Ubuntu High-Performance Computing (ubuntuhpcbot) installed

On a 22.04 machine deployed using Juju (Jammy)

$ snap install slurm --classic --channel latest/candidate
error: cannot perform the following tasks:
- Run install hook of "slurm" snap if present (run hook "install":
-----
Could not find platform independent libraries <prefix>
Could not find platform dependent libraries <exec_prefix>
Python path configuration:
  PYTHONHOME = (not set)
  PYTHONPATH = (not set)
  program name = 'python3'
  isolated = 0
  environment = 1
  user site = 1
  safe_path = 0
  import site = 1
  is in build tree = 0
  stdlib dir = '/usr/lib/python3.12'
  sys._base_executable = '/snap/slurm/417/usr/bin/python3.12'
  sys.base_prefix = '/usr'
  sys.base_exec_prefix = '/usr'
  sys.platlibdir = 'lib'
  sys.executable = '/snap/slurm/417/bin/python3'
  sys.prefix = '/usr'
  sys.exec_prefix = '/usr'
  sys.path = [
    '/usr/lib/python312.zip',
    '/usr/lib/python3.12',
    '/usr/lib/python3.12/lib-dynload',
  ]
Fatal Python error: init_fs_encoding: failed to get the Python codec of the filesystem encoding
Python runtime state: core initialized
ModuleNotFoundError: No module named 'encodings'

Current thread 0x00007f75abe3d300 (most recent call first):
  <no Python frame>
-----)

This needs to be fixed in order for the Slurm snap package to be truly atomic, and make onboarding the current Slurm snap into Charmed HPC easier.

[NucciTheBoss]

This was fixed by reverting to core22. Going forward we'll need to evaluate if we want to continue using Python-based hooks or if we want to change our hooks to another language such as Lua or Go.