Revert 37 pins
~second commit is temporary.~

Closes #27907 

cc @jjhelmus 
what's the trigger condition for the "temporary" commit? > what's the trigger condition for the "temporary" commit?

Those packages being uploaded to the defaults channel by Anaconda (tonight if all goes well). We won't merge this with the second commit. Just testing to ensure there aren't any issues with the packages. Everything seemed to pass using those packages. Reverting the channel commit, which will cause this to fail again. I'll re-run CI once they've been uploaded to defaults. Corrected Python 3.7.4 package are now in `pkgs/main`, CI should now pass if re-run. Something went wrong ... Please have  a look at my logs.