Limit number of parallel GHA runs, print env info in tests

[krfricke]

Unfortunately GHA runs are sometimes aborted due to memory limits. Reducing the number of concurrent trials increases our test time to 2x, but at least these errors stop coming up.

[krfricke]

Well, it seems it doesn't solve the problem. Consider this a draft PR, I'll look into how to fix this later

[amogkam]

Interesting- great catch!

[amogkam]

Though it still looks like 2 of the jobs are failing.

[krfricke]

Yes :-( Maybe we can move this to buildkite?

[amogkam]

Ah sorry, I missed your comment about it not solving the problem. Do you think that it has to do with using the ray cluster fixture with unittest.testCase? Perhaps we should try switching back to pytest for test_colocation.

[krfricke]

I don't think this is related to that, the tests were flaky before that change. I mean, we can try, I'll create a revert PR just in case

[krfricke]

Doesn't seem to be possible from within GitHub. I might try it manually tomorrow

[amogkam]

@krfricke should we merge this?

[krfricke]

Yeah let's do it, though it doesn't solve the problem completely. But it is a good start in any case. Thanks for reminding me!