Update wacz-exhibitor

[rebeccacremona]

See ENG-143 and ENG-170.

This PR updates Perma's dev environment to use the latest version of wacz-exhibitor and makes the recommended changes to nginx.conf.

It also overhauls the wacz-ehibitor docker-compose situation... which I think I basically did entirely incorrectly the first time 😂 . I'm not sure what went wrong there... If I got this right, https://github.com/harvard-lil/docker-compose-update-action will now manage the building, tagging, and pushing of the image to the registry. But honestly I'm a little 🤯 about the whole thing; this syntax might not be exactly right.

[rebeccacremona]

So far so good... although I guess I should have done 0-nohash instead of 1-nohash... Do we care?

[codecov[bot]]

Codecov Report

Merging #3360 (e017405) into develop (f72c36c) will not change coverage. The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop    #3360   +/-   ##
========================================
  Coverage    70.01%   70.01%           
========================================
  Files           52       52           
  Lines         6993     6993           
========================================
  Hits          4896     4896           
  Misses        2097     2097