PERF: Fix performance regression #33365
Fix performance regression in Series.is_monotonic_increasing for categorical
by avoiding Categorical construction for categorical series

- [x] closes #33365
- [x] tests added / passed
- [x] passes `black pandas`
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry: perf regression was introduced after previous version
