Run build during CI

[slifty]

This PR improves our CI to ensure that build + storybook both work before allowing merge. This should make it less likely that we accidentally cause a regression that breaks either build.

Resolves #672

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 47.86%. Comparing base (01d8dba) to head (deaf061).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #911      +/-   ##
==========================================
+ Coverage   47.82%   47.86%   +0.04%     
==========================================
  Files         351      351              
  Lines       11306    11306              
  Branches     1892     1892              
==========================================
+ Hits         5407     5412       +5     
+ Misses       5708     5702       -6     
- Partials      191      192       +1     

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[cecilia-donnelly]

Thank you! Definite improvement.