for gh-49508 changing Doc for DataFrame.astype
added the series in input in the doc of DataFrame.astype

closes #49508 


> Also appears to be some code check failures

Thanks I'll fix them up Done the changes sir Looks to be some validation errors:

```
Error: /home/runner/work/pandas/pandas/pandas/core/generic.py:5999:PR06:pandas.DataFrame.astype:Parameter "dtype" type should use "str" instead of "string"
Error: /home/runner/work/pandas/pandas/pandas/core/generic.py:5999:PR06:pandas.Series.astype:Parameter "dtype" type should use "str" instead of "string"
``` > Looks to be some validation errors:
> 
> ```
> Error: /home/runner/work/pandas/pandas/pandas/core/generic.py:5999:PR06:pandas.DataFrame.astype:Parameter "dtype" type should use "str" instead of "string"
> Error: /home/runner/work/pandas/pandas/pandas/core/generic.py:5999:PR06:pandas.Series.astype:Parameter "dtype" type should use "str" instead of "string"
> ```

Sir I didn't understand how can a validation error come from line 5999 when I did not even change the line, seems strange. This is a shared docstring so it's used by 2 other functions. I think `string` should be be `str` as mentioned in the message > This is a shared docstring so it's used by 2 other functions. I think `string` should be be `str` as mentioned in the message

thanls sir done the changes Thanks @ramvikrams  > Thanks @ramvikrams

Thank you sir for your help all along