bumps sphinx and myst-parser pinned versions to play nicely with Python 3.13

[benjamin-white-233]

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Fixes #1807

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Summarize your change.

Building docs on Python 3.13 fails due to Sphinx pinned version requiring imghdr which is deprecated in newer python versions as of 3.13 (deprecated but available in 3.12).

Bumping pinned versions sphinx==7.3.7 and myst-parser==3.0.1 allows building docs on Python 3.13.

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[linux-foundation-easycla]

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 81.63%. Comparing base (c0e97b0) to head (93b5433).
⚠️ Report is 93 commits behind head on main.

❌ Your changes status has failed because you have indirect coverage changes. Learn more about Unexpected Coverage Changes and reasons for indirect coverage changes.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1815      +/-   ##
==========================================
- Coverage   84.11%   81.63%   -2.49%     
==========================================
  Files         198      176      -22     
  Lines       22241    12683    -9558     
  Branches     4687     2784    -1903     
==========================================
- Hits        18709    10354    -8355     
+ Misses       2610     1783     -827     
+ Partials      922      546     -376     

Flag	Coverage Δ
py-unittests	81.63% <ø> (-2.49%)	⬇️

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see 123 files with indirect coverage changes

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[reinecke]

It looks like the build is failing on:

WARNING: Calling get_html_theme_path is deprecated. If you are calling it to define html_theme_path, you are safe to remove that code.

Perhaps this is a new deprecation in the updated versions?