update ammo kill to 2 metroids

Author: blkerby

region/tourian/main/Metroid Room 1.json

@@ -554,7 +554,7 @@
       "requires": [
         "Ice",
         {"enemyKill": {
-          "enemies": [["Metroid", "Metroid", "Metroid", "Metroid"]],
+          "enemies": [["Metroid", "Metroid"]],
           "explicitWeapons": ["Super", "Missile"]
         }}
       ],