DOC: fix RT03 error for pandas.DataFrame.hist
- [ ] ~~closes https://github.com/pandas-dev/pandas/issues/56804~~ (Not relevant, it is a RT03 error )
- [x] All [code checks passed](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#pre-commit).

~~Detected EX03 error for `pandas.DataFrame.hist`:~~
```
python scripts/validate_docstrings.py --format=actions --errors=EX03 pandas.DataFrame.hist
```
Output:
```
################################################################################
################################## Validation ##################################
################################################################################

1 Errors found for `pandas.DataFrame.hist`:
        Return value has no description
```

The output after this changes:
```
################################################################################
################################## Validation ##################################
################################################################################

Docstring for "pandas.DataFrame.hist" correct. :)
```
This pull request is stale because it has been open for thirty days with no activity. Please [update](https://pandas.pydata.org/pandas-docs/stable/development/contributing.html#updating-your-pull-request) and respond to this comment if you're still interested in working on this. This seems stale and conflicting, closing. Thanks for the work on this @erichxchen, if you have the time to finish this, or to work on other contributions, you're very welcome to do so. 