[MIRROR] adds missing SIGNAL_HANDLERs (#10768)

Co-authored-by: SatinIsle <98125273+SatinIsle@users.noreply.github.com>

code/unit_tests/clothing_tests.dm

@@ -149,6 +149,7 @@
 	return failed
 
 /datum/unit_test/all_clothing_shall_be_valid/get_signal_data(atom/source, list/data = list())
+	SIGNAL_HANDLER
 	switch(data[1])
 		if("set_slot")
 			var/slot_name 	= data[2]

code/unit_tests/reagent_tests.dm

@@ -280,6 +280,7 @@
 	return TRUE
 
 /datum/unit_test/chemical_reactions_shall_not_conflict/get_signal_data(atom/source, list/data = list())
+	SIGNAL_HANDLER
 	result_reactions.Add(data[1]) // Append the reactions that happened, then use that to check their inhibitors