[MIRROR] Weakref cleanup (#12704)

Co-authored-by: Will <7099514+Willburd@users.noreply.github.com>
Co-authored-by: Cameron Lennox <killer65311@gmail.com>

code/modules/organs/data.dm

@@ -17,6 +17,10 @@
 	var/list/skin_color
 	var/list/hair_color
 
+/datum/organ_data/Destroy(force)
+	. = ..()
+	species = null
+
 /datum/organ_data/proc/setup_from_dna(var/datum/dna/dna)
 	SHOULD_NOT_OVERRIDE(TRUE)
 	// Prosfab uses default dna to get vars, lets respect that still