Fix documentation build

[chrisjonesBSU]

PR Summary:

The doc builds were failing with sphinx>=8.0. This PR fixes the source of the error.

PR Checklist

---

• Includes appropriate unit test(s)
• Appropriate docstring(s) are added/updated
• Code is (approximately) PEP8 compliant
• Issue(s) raised/addressed?

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 61.88%. Comparing base (2707210) to head (32c78d9).
Report is 13 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #592      +/-   ##
==========================================
- Coverage   62.04%   61.88%   -0.17%     
==========================================
  Files          16       16              
  Lines        1665     1658       -7     
==========================================
- Hits         1033     1026       -7     
  Misses        632      632