Make Installation Easier

[robertdstein]

I often use flarestack downstream as a dependency, and noticed that it has become harder to install.

This PR converts photospline to an optional dependency (you only get the import error when you actually try and use photosopline).

It also does a couple of other quality of life bug fixes:

• Splits off black into a separate CI test, and tests black using pinned local version, and moves the black version to "dev" dependency in pyproject.toml (fix use black 2024 #347)
• Adds support for python 3.12 (after bumping photospline version)

python 3.13 is still too hard because of #270, but once that's fixed you can bump scipy to a higher version and add python 3.13 support.

[mlincett]

That is a good idea, I had suggested it when photospline was added as dependency.

In principle the psf/black action can read the version from pyproject.toml so it should not be necessary to use the workaround we have in place.

[JannisNe]

Looks good. My only comment is that we should either both test and build for python 3.9 or if we do not build that version then there is also no need to test it.

[robertdstein]

@mlincett do you want me to move it back to the github action black? My thinking was that the new setup is cleaner, since there is exactly one thing pinned (black python version), and any changes are automatically bumped by dependabot. It's a also cleaner template to add in other auto-linting e.g isort. But if you prefer the old method I can do that.

[mlincett]

@mlincett do you want me to move it back to the github action black? My thinking was that the new setup is cleaner, since there is exactly one thing pinned (black python version), and any changes are automatically bumped by dependabot. It's a also cleaner template to add in other auto-linting e.g isort. But if you prefer the old method I can do that.

Sorry, I thought I had answered but it was just a draft in my mind. As we have a setup that works, no need to overthink at the moment.