CI: Fixed travis-36-cov build
Closes #30309 

Just debugging right now. Can't reproduce locally yet.
In theory, setting `LD_PRELOAD=/opt/conda/lib/libgomp.sov` will fix this. Trying to understand the issue a bit more first. Rather than updating that may also just want to get off of the trusty service since may have been patched in glibc

https://github.com/pytorch/pytorch/issues/2575#issuecomment-523667875

 Mmm good to know.

I think we had issues with databases last time I looked. Will see if I can find that thread. The LD_LIBRARY_PRELOAD thing did the trick, but I'd prefer to solve it more cleanly. Trying Will's suggestion next. I think also need to add the appropriate DB services for CI to be green:

https://docs.travis-ci.com/user/database-setup/#mysql Whoops sorry I see you did that one some already, but I guess that's what is causing the CI failure for the ones currently red Yep, I have a commit to fix that, just waiting for the running job to see if the openmp thing is fixed.  OK that one passed. Took 34 minutes though, compared to 27 in https://travis-ci.org/pandas-dev/pandas/builds/626386764 :/ Hmm yea something watch, though I think the runs normally fluctuate in that range Thanks for the help Will! I'm glad to have avoided the LD_LIBRARY_PRELOAD stuff.

This last run took 32 minutes. I recall some ongoing work to balance these builds a bit, will see if I can track that down.