DOC: fix docstring typo

[mgyist]

Pandas version checks

• I have checked that the issue still exists on the latest versions of the docs on main here

Location of the documentation

https://github.com/pandas-dev/pandas/blob/main/pandas/core/dtypes/dtypes.py

Documentation problem

There seem to be two extra words in the is_dtype method docstring, both in the PeriodDtype and IntervalDtype classes:

@classmethod
    def is_dtype(cls, dtype: object) -> bool:
        """
        Return a boolean if we if the passed type is an actual dtype that we
        can match (via string or type)
        """

Suggested fix for documentation

Remove the words 'if we' in both places.

[arthurlw]

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