TYP: changed variable hashed to combined_hashed in dtype.py (#44360)

* changed variable hashed to combined_hashed in dtype.py

* pre-commit changes

Author: nickleus27

pandas/core/dtypes/dtypes.py

@@ -468,12 +468,8 @@ def _hash_categories(self) -> int:
             # error: Incompatible types in assignment (expression has type
             # "List[ndarray]", variable has type "ndarray")
             cat_array = [cat_array]  # type: ignore[assignment]
-        # error: Incompatible types in assignment (expression has type "ndarray",
-        # variable has type "int")
-        hashed = combine_hash_arrays(  # type: ignore[assignment]
-            iter(cat_array), num_items=len(cat_array)
-        )
-        return np.bitwise_xor.reduce(hashed)
+        combined_hashed = combine_hash_arrays(iter(cat_array), num_items=len(cat_array))
+        return np.bitwise_xor.reduce(combined_hashed)
 
     @classmethod
     def construct_array_type(cls) -> type_t[Categorical]: