API: Index.__array_wrap__ stop special-casing bool dtype

[jbrockmendel]

For the "just do in 3.0" pile. Index.__array_wrap__ reads

    def __array_wrap__(self, result, context=None):
        """
        Gets called after a ufunc and other functions e.g. np.split.
        """
        result = lib.item_from_zerodim(result)
        if is_bool_dtype(result) or lib.is_scalar(result) or np.ndim(result) > 1:
            return result

        return Index(result, name=self.name)

The is_bool_dtype check is left over from before we supported bool-dtype Indexes. Affected tests are pandas/tests/indexes/test_numpy_compat.py::test_numpy_ufuncs_other