Lesser drone CRASH hotfix (#5037)

# About the pull request

Fixes a `CRASH()` when the lesser drone gets gibbed...

# Explain why it's good for the game
# Testing Photographs and Procedure
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# Changelog
:cl:
fix: Fix lesser drone crash on getting gibbed.
/:cl:

code/modules/mob/living/carbon/xenomorph/castes/lesser_drone.dm

@@ -98,7 +98,7 @@
 
 /mob/living/carbon/xenomorph/lesser_drone/ghostize(can_reenter_corpse = FALSE, aghosted = FALSE)
 	. = ..()
-	if(. && !aghosted)
+	if(. && !aghosted && !QDELETED(src))
 		gib()
 
 /mob/living/carbon/xenomorph/lesser_drone/handle_ghost_message()