Add bundle analyzer dashboard to track js assets over time

[zephraph]

This is a trial of the bundle-analyzer dashboard service. It's a free service that provides a dashboard to track bundle asset changes over time.

It may and/or may not be useful. We'll remove it again if it proves not to be useful.

[codecov]

Codecov Report

Merging #4684 into master will decrease coverage by <.1%.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           master   #4684     +/-   ##
========================================
- Coverage    79.3%   79.2%   -0.1%     
========================================
  Files        1268    1268             
  Lines       35050   35291    +241     
  Branches     1992    2029     +37     
========================================
+ Hits        27799   27976    +177     
- Misses       6226    6263     +37     
- Partials     1025    1052     +27

[zephraph]

I haven't been able to get the size checks to pick up, but that might require the config to be in master. I remove the bundlesizes check to reduce redundancy between the service checks.

What do you think @alloy? Want to try it out for a bit?

[alloy]

Sure, let’s do it 👍