Fix `bilby_pipe` test in the testing suite
It seems that the bilby_pipe test is failing because:
bilby_pipe: error: argument --trigger-time: invalid <bilby_pipe.utils.NoneWrapper object at 0x7ff36cca07f0> value: 'GW150914'It seems that the bilby_pipe test is failing because:
bilby_pipe: error: argument --trigger-time: invalid <bilby_pipe.utils.NoneWrapper object at 0x7ff36cca07f0> value: 'GW150914'