Can't update our CI to use 24.04 because of installation in system python

[kimwnasptd]

Bug Description

In 24.04 the Python version includes PEP668

The following PEP disallows by default to install packages in the system-wide python installation.
https://stackoverflow.com/questions/77676556/whats-the-correct-way-to-use-user-local-python-environment-under-pep668

In order to use 24.04 and onwards we'll need to always use virtual environments to avoid this issue

To Reproduce

1. Bump Ubuntu version to 24.04 in any of our CI

Environment

Any of our repos that

1. doesn't use 24.04 for testing
2. doesn't create a virtual environment for running the tests

Relevant Log Output

$ pip install setuptools --user
error: externally-managed-environment

× This environment is externally managed
╰─> To install Python packages system-wide, try apt install
    python3-xyz, where xyz is the package you are trying to
    install.
    
    If you wish to install a non-Debian-packaged Python package,
    create a virtual environment using python3 -m venv path/to/venv.
    Then use path/to/venv/bin/python and path/to/venv/bin/pip. Make
    sure you have python3-full installed.
    
    If you wish to install a non-Debian packaged Python application,
    it may be easiest to use pipx install xyz, which will manage a
    virtual environment for you. Make sure you have pipx installed.
    
    See /usr/share/doc/python3.11/README.venv for more information.

note: If you believe this is a mistake, please contact your Python installation or OS distribution provider. You can override this, at the risk of breaking your Python installation or OS, by passing --break-system-packages.
hint: See PEP 668 for the detailed specification.

Additional Context

This is not the case for 22.04

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Thank you for reporting us your feedback!

The internal ticket has been created: https://warthogs.atlassian.net/browse/KF-6208.

This message was autogenerated

[mvlassis]

Let's keep in mind that we want to keep the same version of Ubuntu as the one we use for building/running the charms.

[kimwnasptd]

We saw the same issue with using tox in the charmed-actions charmed-kubernetes/actions-operator#82

The suggested approach there is to use virtual environments as discussed above.

[jnsgruk]

FWIW I solved this problem in these two commits:

• jnsgruk/zinc-k8s-operator@e6f9a45
• jnsgruk/zinc-k8s-operator@e2efc4f

[addyess]

@kimwnasptd try again now that actions-operator and pytest-operator have been updated to support this better