Update package.json

Author: songyumeng

src/leaflet/package.json

@@ -22,7 +22,7 @@
     "@mapbox/vector-tile": "1.3.1",
     "jsonsql": "0.2.5",
     "pbf": "3.2.1",
-    "proj4": "2.6.2",
+    "proj4": "2.6.3",
     "xlsx": "0.16.8"
   }
 }