Remove the python<3.12 requirement

Notes

• Python 3.12 has fully removed distutils as part of the Python standard library. Instead, setuptools provides its own internal distutils module.
• psydac supports python3.12 since https://github.com/pyccel/psydac/pull/424
• sympde requires python < 3.13 https://github.com/pyccel/sympde/blob/master/pyproject.toml#L10

Now, scheduled CI pipelines can be started from Gitlab by clicking Pipelines --> Run Pipeline, there you can set up the following variables:

variables:
  MAKE_PAGES:
    value: "false"
    options: ["true", "false"]
    description: "''true'' to make pages"
  TEST_SCHEDULED:
    value: "false"
    options: ["true", "false"]
    description: "''true'' to run the scheduled pipeline"
  STRUPHY_SOURCE_DOCKER:
    value: "dist/struphy*.whl"
    options: ["dist/struphy*.whl", "-U struphy"]
    description: "Source to install struphy from in the docker jobs."

The variables used in each pipeline can be checked in the ci_vars job

Solves the following issue(s):

Closes #362 (closed) #356 (closed)

Core changes:

• Removed the <3.12 requirement for python
• Updated the CI to use variables for running the scheduled pipeline and make pages pipeline
  • make pages pipeline
  • Scheduled pipeline with STRUPHY_SOURCE_DOCKER=dist/struphy*.whl
  • Scheduled pipeline with -U struphy

Model-specific changes:

None

Documentation changes:

None