Align MANIFEST.in with templating

[trexfeathers]

https://github.com/SciTools/.github/blob/main/templates/README.md

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 57.61%. Comparing base (fcbb461) to head (effc8b7).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #608   +/-   ##
=======================================
  Coverage   57.61%   57.61%           
=======================================
  Files          61       61           
  Lines        6293     6293           
  Branches     1150     1150           
=======================================
  Hits         3626     3626           
  Misses       2376     2376           
  Partials      291      291           

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[trexfeathers]

I have tested this change locally using the python-build package.

Files newly included in a cf-units source distribution (sdist)

NONE

Files no longer included in a cf-units source distribution (sdist)

• .git_archival.txt
• .gitattributes
• .pre-commit-config.yaml
• .readthedocs.yml
• CODE_OF_CONDUCT.md
• codecov.yml
• docs/Makefile
• docs/make.bat
• docs/source/conf.py
• docs/source/index.rst
• docs/source/unit.rst
• docs/source/utilities.rst
• requirements/README.md
• requirements/cf-units.yml
• requirements/locks/README.md
• requirements/locks/py310-lock-linux-64.txt
• requirements/locks/py310-lock-osx-64.txt
• requirements/locks/py310-lock-win-64.txt
• requirements/locks/py311-lock-linux-64.txt
• requirements/locks/py311-lock-osx-64.txt
• requirements/locks/py311-lock-win-64.txt
• requirements/locks/py312-lock-linux-64.txt
• requirements/locks/py312-lock-osx-64.txt
• requirements/locks/py312-lock-win-64.txt
• requirements/locks/py313-lock-linux-64.txt
• requirements/locks/py313-lock-osx-64.txt
• requirements/locks/py313-lock-win-64.txt

[HGWright]

Thanks @trexfeathers