Update upstream-dev testing infrastructure

[dcherian]

Xarray has a fancy new nightly upstream testing workflow.

It runs nightly and opens nice issues with test logs (example). It'd be nice to copy that over here so things like #652 can be caught more proactively.

[snowman2]

Sounds great. Current state of rioxarray latest testing: https://github.com/corteva/rioxarray/blob/d492a2ad1eeafd9836ceec87a109e0d2645fd3eb/.github/workflows/tests.yaml#L165-L212

[snowman2]

The issue with latest was that the build failed often due to installation issues or other noise that unfortunately made it less useful. It just barely stabilized enough to get useful testing information.

[Zeitsperre]

That's really cool! @dcherian mind if I grab that for xclim?

[dcherian]

@Zeitsperre go for it!

The cf-xarray version also supports adding a test-upstream label.