Attempt to fix docs build

[daico007]

PR Summary:

Currently mbuild docs is stuck at v0.14.2. This PR will attempt to trace the errors in the docs build and fix them.

PR Checklist

---

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

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 87.28%. Comparing base (e919ca4) to head (b9f45de).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1169 +/- ## ======================================= Coverage 87.27% 87.28% ======================================= Files 62 62 Lines 6499 6502 +3 ======================================= + Hits 5672 5675 +3 Misses 827 827 ```

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