TST: add test to confirm adding 'm' to a Series of strings does not error
adds a test to check for regressions later.   Replacement PR for #28732

- [ X ] closes #28658 
- [ X ] tests added / passed
- [ X ] passes `black pandas`
- [ X ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ -  ] whatsnew entry
