Maintenance upgrades

[corviday]

This PR upgrades to Ubuntu 24.04, GDAL 3.8, and Python 3.12.

Python 3.12 heavily encourages users to install libraries into a virtual environment such as pipx, poetry, or venv. However, in this case, which creates a single-purpose docker container as a base for specific applications, I think we are justified to use the --break-system-packages argument to override 3.12's preferences; we're not concerned about any hypothetical other python applications getting their dependencies scrambled by a systemwide python library install.

(Draft until we've verified that other applications built on top of this still work.)

[jameshiebert]

I think that it's pretty reasonable to use the --break-system-packages in this context. Though, I'm curious if you considered changing the image to be such that it just provides a poetry environment that has everything installed.

[corviday]

I considered it, but I thought the extra flexibility from not requiring any specific virtual environment might be useful someday. Happy to switch up the strategy here if we decide otherwise.

[rod-glover]

Agreed that it seems reasonable to use --break-system-packages in this instance. Assuming you know that existing downstream users of this image work, I say go ahead and merge.

[corviday]

Other repositories using this docker image:

• climate-explorer-backend has been updated to use this branch
• sandpiper has been updated to use this branch
• portainer-deployment - did at one point deploy an older version of this image, but I think that was to test something that has since been resolved, and we don't need to keep deploying the old image
• climate-explorer-netcdf-tests is not in active use
• repotrack- is tracking the status of maintenance updates and does not actually deploy this image
• docker-guniflask - is not in active use
• pydap-test is not in active use

So as far as I can tell, the only two repositories that currently deploy this image are climate-explorer-backend and sandpiper, both of which have been updated to use this version.