Use strings for map json trainer_type and trainer_sight_or_berry_tree_id fields

data/maps/BattleFrontier_BattlePikeCorridor/map.json

@@ -22,8 +22,8 @@
       "movement_type": "MOVEMENT_TYPE_FACE_DOWN",
       "movement_range_x": 1,
       "movement_range_y": 1,
-      "trainer_type": 0,
-      "trainer_sight_or_berry_tree_id": 0,
+      "trainer_type": "0",
+      "trainer_sight_or_berry_tree_id": "0",
       "script": "0x0",
       "flag": "0"
     }