Add missing translation for the rainboom death message. Fixes #501

src/main/resources/assets/unicopia/lang/en_us.json

@@ -1637,6 +1637,8 @@
   "death.attack.unicopia.bat_screech.self": "%1$s spooked themselves",
   "death.attack.unicopia.bat_screech.player": "%2$s spooked %1$s",
   "death.attack.unicopia.bat_screech.item": "%1$s was spooked by %2$s using %3$s",
+  "death.attack.unicopia.rainboom": "%1$s's eardrums were shattered",
+  "death.attack.unicopia.rainboom.player": "%2$s's shattered %1$s's eardrums",
   "death.attack.unicopia.gravity_well_recoil": "%1$s turned into spaghetti",
   "death.attack.unicopia.gravity_well_recoil.player": "%1$s turned into spaghetti by a spell cast by %2$s",
   "death.attack.unicopia.gravity_well_recoil.item": "%1$s turned into spaghetti by a spell cast by %2$s using %3$s",