TST: insert 'match' to bare pytest raises in pandas/tests/tseries/off…
…sets/test_ticks.py

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

ref: https://github.com/pandas-dev/pandas/issues/30999
Please have look at this PR. I am new to this, I have tried to follow guidelines as much as possible.

FYI @MomIsBestFriend 
