Add Sphinx extension for measuring durations in doc builds - #2268

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Codecov Report

Patch and project coverage have no change.

Comparison is base (41887c4) 98.37% compared to head (ca633c4) 98.37%.
Report is 1 commits behind head on main.

❗ Current head ca633c4 differs from pull request most recent head 70f578e. Consider uploading reports for the commit 70f578e to get more accurate results

@@           Coverage Diff           @@
##             main    #2268   +/-   ##
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  Coverage   98.37%   98.37%           
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  Files          98       98           
  Lines        8533     8533           
=======================================
  Hits         8394     8394           
  Misses        139      139           

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Merging this since it's a minimal change, and I plan to use it for another PR too.