[NO GBP] ...Remember to add SIGNAL_HANDLER (#82630)

## About The Pull Request

Just realized I forgot to add `SIGNAL_HANDLER` to the all-nighter
`on_removed_limb(...)` proc, even though it handles signals.
## Why It's Good For The Game


https://github.com/tgstation/tgstation/blob/fe26373572e41415ec12e2b0785f0c6dc2567577/code/__DEFINES/dcs/helpers.dm#L9-L11

code/datums/quirks/negative_quirks/all_nighter.dm

@@ -43,6 +43,8 @@
 
 ///if we have bags and lost a head, remove them
 /datum/quirk/all_nighter/proc/on_removed_limb(datum/source, obj/item/bodypart/removed_limb, special, dismembered)
+	SIGNAL_HANDLER
+
 	if(bodypart_overlay && istype(removed_limb, /obj/item/bodypart/head))
 		remove_bags()