Drop duplicate indices
- [x] closes #58648
- [ ] [Tests added and passed](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#writing-tests) if fixing a bug or adding a new feature
- [x] All [code checks passed](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#pre-commit).
- [x] Added [type annotations](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#type-hints) to new arguments/methods/functions.
- [x] Added an entry in the latest `doc/source/whatsnew/vX.X.X.rst` file if fixing a bug or adding a new feature.

Tests are added but have not been run, as I get this error when I try to run them. I tried all envorment setup options but I end-up having the same error

```shell
root@92c4f0dec9a0:/home/pandas# pytest pandas/tests/frame/methods/test_drop_duplicates.py
ImportError while loading conftest '/home/pandas/pandas/conftest.py'.
pandas/__init__.py:47: in <module>
    from pandas.core.api import (
pandas/core/api.py:46: in <module>
    from pandas.core.groupby import (
pandas/core/groupby/__init__.py:1: in <module>
    from pandas.core.groupby.generic import (
pandas/core/groupby/generic.py:1418: in <module>
    class DataFrameGroupBy(GroupBy[DataFrame]):
pandas/core/groupby/generic.py:2571: in DataFrameGroupBy
    @doc(DataFrame.plot.__doc__)
E   AttributeError: type object 'DataFrame' has no attribute 'plot'
```
Most of these tests are failing because of the same error mentioned earlier
```bash
AttributeError: type object 'DataFrame' has no attribute 'plot'
```

others like precommit fail from parts that I haven't edited Thanks for the pull request, but it appears to have gone stale. If interested in continuing, please merge in the main branch, address any review comments and/or failing tests, and we can reopen.