Update to TLJH 1.0, tljh-repo2docker==1.0.2, Ubuntu 24.04

[jtpio]

Trying to perform a more minimal update than #224, as #224 requires more work to be fully working.

Fixes #227

Note

The most relevant change from this update to fix #227 is the bump to tljh-repo2docker==1.0.2 which includes plasmabio/tljh-repo2docker#103.
But since tljh-repo2docker==1.0.2 also updated to JupyterHub 4, this PR updates to TLJH 1.0 (based on JupyterHub 4)

Testing with plasmabio/template-python#13 which updates to JupyterHub 4

• Update to a pinned version of the TLJH installer (v1): https://tljh.jupyter.org/en/latest/howto/admin/upgrade-tljh.html#step-3-make-the-upgrade
• Update to JupyterHub 4
• Use pytest-jupyterhub for the tests
• Drop Python 3.8 in the tests
• Update playbooks to new ubuntu and docker
• Document new requirements:
  • Ubuntu 24.04
  • TLJH 1.0

[jtpio]

Using a test image from plasmabio/template-python#13, and the changes from the last commit of this PR:

plasma-fix-TLJH-1.mp4

[pierrepo]

Thanks @jtpio this looks good