Assign *value* to the boolean child *name* of `w:rPr`.

def _set_bool_prop(self, name, value):
        """
        Assign *value* to the boolean child *name* of `w:rPr`.
        """
        rPr = self._element.get_or_add_rPr()
        rPr._set_bool_val(name, value)