TST: Use fixtures in indexes common tests
- [x] closes #16835
- [x] tests added / passed
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

Not sure if there is a better way to define fixture params since they're essentially the indexes defined in `setup_method`. Also thinking about adding an id to each param so the output doesn't look like:

```
test_base.py::TestMixedIntIndex::test_sort[index0] <- pandas/tests/indexes/common.py PASSED
test_base.py::TestMixedIntIndex::test_sort[index1] <- pandas/tests/indexes/common.py PASSED
test_base.py::TestMixedIntIndex::test_sort[index2] <- pandas/tests/indexes/common.py PASSED
test_base.py::TestMixedIntIndex::test_sort[index3] <- pandas/tests/indexes/common.py PASSED
...
```