 TYP: Add MyPy Error Codes
- [ ] closes #29197
- [ ] tests added / passed
- [ ] passes `black pandas`
- [ ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

@WillAyd have added a code-check to enforce this but may not be able to enable until we bump mypy due a bug in mypy not suppressing some additional notes, so have just commented out the code check for now @WillAyd gentle ping! Thanks @simonjayhawkins 