Add patch version to site/go.mod

[sjberman]

Problem: As of Go 1.21, toolchain versions must use the 1.N.P syntax. This is causing a warning from CodeQL in our pipelines.

Solution: Add the minimum patch version.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.74%. Comparing base (8cf2608) to head (d007b0c).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2934   +/-   ##
=======================================
  Coverage   89.74%   89.74%           
=======================================
  Files         109      109           
  Lines       11150    11150           
  Branches       50       50           
=======================================
  Hits        10007    10007           
  Misses       1083     1083           
  Partials       60       60           

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