[ready] unit tests all worn icons (#72370)

Fixes #71692

🆑 ShizCalev
code: Added a unit test for ALL worn icons.
fix: Fixed a bunch of broken worn icons!
/🆑

code/modules/instruments/piano_synth.dm

@@ -56,6 +56,7 @@
 	name = "\improper Nanotrasen space pods"
 	desc = "Flex your money, AND ignore what everyone else says, all at once!"
 	icon_state = "spacepods"
+	worn_icon = 'icons/mob/clothing/ears.dmi'
 	inhand_icon_state = null
 	slot_flags = ITEM_SLOT_EARS
 	strip_delay = 100 //air pods don't fall out