Update CircleCI Python several versions for future proofing

[clairekope]

Addresses #222

[gregbryan]

Maybe try "-std=legacy" in Fortran compile?

[clairekope]

That's certainly an easier flag. Though for some reason it's not being passed when ffte4X.F90 is getting compiled...

[gregbryan]

The problem is that the answer testing works by compiling a version with the current gold-standard (which does not have this flag) and then compiling a version with this PR changes. The PR changes are clearly working because the test-compile-options test passes, but the first step of the test-suite (compilation of the current gold-standard) is the thing that is failing. There is no way to fix that in a PR except by updating the gold-standard. I think that is probably what we need to do, go from gold-standard-15 to gold-standard-16. Unfortunately, this takes a few steps which are outlined here: enzo-project/enzo-e#307

[clairekope]

I did not realize that the gold standard version was also compiled. I'll create a new issue for tracking the gold standard update.

[clairekope]

I've pushed a lightweight tag as part of this PR that should switch the gold standard to building with -std=legacy (at least for the ubuntu machine file)

[gregbryan]

Thanks Claire! Now it looks like it is failing due to a pynose problem. I'm guessing that you may need to bump dependencies-v3 to dependencies-v4 in config.yml to clear the dependencies cache, since you bumped the CircleCI image.

[clairekope]

Tried Python 3.10.13, but nose might still not work (xlcnd/isbnlib#95) despite the issues of not(?) having python3 in the circleci image?

[clairekope]

Path forward: return to the 3.11.5 image and migrate from nose to pytest. Nose hasn't been updated since 2015 anyway. Added as issue #229

[clairekope]

Tests passed but there are unyt errors in the reference tests

[clairekope]

12 of the reference tests fail due to a change with unyt v3. This is fixed by a PR on yt: yt-project/yt#4764

There is also an issue that, when comparing the new version of Enzo to the standard, the standard's answers don't seem to be saved.

[clairekope]

I have figured out the nuances of CircleCI. For future reference:

• when updating software versions for the test toolchain, make sure to update the dependency cache or you will get a vague error about a missing Python executable
• when updating the gold standard, first update the CircleCI config to use this new standard: update the reference/answer tag as well as the name for the answer cache. Commit these changes to the config file and attach a git tag to this same commit. Placing a tag on an older commit than the one where the CircleCI config was updated will mean CircleCI will not cache answers correctly.

To maintainers:
Please please please squash these commits when merging.

[gregbryan]

Looks good to me -- thanks Claire for persevering though all of that!

[bwoshea]

Looks good to me!

[bwoshea]

Looks great, I'm approving and merging.