UI related to gstlal_itacac.c
I attempted to run a dag for the O3GK all-sky search while I expected gstlal_inspiral to fail at the itacac part since it hasn't had the G1 detector yet. However, it didn't fail. So I ran one of the gstlal_inspiral jobs separately with the GST_DEBUG option and found that gstlal_itacac.c actually detected the issue as follows
0:00:21.795395471 151352 0x3be8ed0 ERROR lal_itacac gstlal_itacac.c:208:get_instrument_pad_pointer:gstlalitacac0:sink_0 pad has unknown detector, G1
at get_instrument_pad_pointer, but it isn't treated as a fatal error. I think we should make the issue fatal with g_assert or in some other appropriate ways so that the main program is immediately aborted in detection of this error. I would like to hear other people's opinions about this.