TST: series/indexing tests parameterization + moving test methods
Parts 2 and 3 of #20014. 
- tests parameterization
- moving some tests from test_indexing.py to other files 
- test methods reordering in test_indexing.py

- [x] closes #20014
- [x] tests added / passed
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
