Pandas BUG: SparseArray.map allows the fill value to be included in the sparse values

Pandas version checks

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Reproducible Example

>>> import pandas as pd
>>> sp = pd.arrays.SparseArray([1, np.nan])
>>> mapped = sp.map(lambda x: np.nan)
>>> pd.isna(mapped.fill_value)
True
>>> pd.isna(mapped.sp_values)[0]
True

Issue Description

The current implementation of SparseArray.map allows the fill value to be included in the sparse values, causing potential problems.

Expected Behavior

SparseArray.map It should raise or recalculate the sparse array.

Installed Versions

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