Improve claude testing instructions

[mfosterw]

I updated the command but forgot to update claude's docs, and none of the automatic review caught it.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (73d0d51) to head (20878ef).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #324   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           49        49           
  Lines         2017      2017           
=========================================
  Hits          2017      2017           

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