CLN: test_intersect_str_dates appears to have been mistakenly placed in tests/indexes/test_range.py
#### Code Sample, a copy-pastable example if possible
https://github.com/pandas-dev/pandas/blob/36dadd70376c6033037af281a4669a360fc71cfa/pandas/tests/indexes/test_range.py#L642-L649

#### Problem description
The `test_intersect_str_dates` test within `tests/indexes/test_range.py` doesn't appear to have anything to do with `RangeIndex`.  It seems like this should be moved to `tests/indexes/test_base.py`?  Happy to submit a PR  if this is the case.