Add gates in test workflows

[mtfishman]

Adds a final "gate" on the test workflows that pass or fail based on the overall results of the testing matrix. That is helpful for having a single point of detecting the overall status of tests, for example for branch protection rules.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 78.68%. Comparing base (368a3e2) to head (e726c24).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #117   +/-   ##
=======================================
  Coverage   78.68%   78.68%           
=======================================
  Files          12       12           
  Lines         793      793           
=======================================
  Hits          624      624           
  Misses        169      169           

Flag	Coverage Δ
docs	30.20% <ø> (ø)

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