Update conda installation action

[APJansen]

I happened to look at the failing tests in #1929 on my phone, and there I saw a hint which I don't see on my laptop, which was to update the action that sets up conda, hope this fixes the tests that I think will fail now on master as well when rerun.

[RoyStegeman]

You may want to have a look at #1928

[Cmurilochem]

Just another hint: Maybe the actions/checkout@v1 could also be updated. Currently we are in actions/checkout@v4. Sorry, just saw that this has been considered in #1928.

[APJansen]

You may want to have a look at #1928

Sorry I missed that

I saw the libmamba solver has a new version released last week, so at least timing wise it seems like that could be the issue. Unfortunately downgrading that to the previous version also doesn't solve it.

[APJansen]

I found someone else with the same issue
He suggests downgrading conda-build to 3.28.4, I'm not sure how to do that?
Also created a minimal example that reproduces it.

[scarlehoff]

I also have no idea what is happening.
Since due to licence issues I cannot (or should not) use the anaconda repos I've tried to do at the same time an update to conda-forge and updating the workflows.

That seems to work for linux but mac is still broken #1932

[scarlehoff]

I found someone else with the same issue He suggests downgrading conda-build to 3.28.4, I'm not sure how to do that? Also created a minimal example that reproduces it.

Thanks! I've done this in #1932 (only for mac) and it seemed to work :D
Now mac is quite pinned while linux is freer than before, but as I said, hopefully most of this will be gone soon.