Surface Transforms cannot be unset.

[MicahGale]

This was found during #709.

The suspect code is in montepy.surfaces.surface

    def _update_values(self):
        modifier = self._tree["surface_num"]["modifier"]
        if self.is_reflecting:
            modifier.value = "*"
        elif self.is_white_boundary:
            modifier.value = "+"
        else:
            modifier.value = ""
        if self.transform is not None:
            self._old_transform_number.value = self.transform.number
            self._old_transform_number.is_negative = False
            self._tree.nodes["pointer"] = self._old_transform_number
        elif self.periodic_surface is not None:
            self._old_periodic_surface.value = self.periodic_surface.number
            self._old_periodic_surface.is_negative = True
            self._tree.nodes["pointer"] = self._old_periodic_surface

If self.transorm is None there is no way to update the transform/periodic_surface number to be None. This will require a slight redesign and testing that I can't do right now.

[MicahGale]

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