chore: clean up package.json files field

Remove invalid /web/ paths (files are in build/web/, already included
via build) and remove leading slashes from paths.

Author: STRML

package.json

@@ -18,10 +18,8 @@
     "flow": "flow"
   },
   "files": [
-    "/build",
-    "/typings",
-    "/web/react-draggable.min.js",
-    "/web/react-draggable.min.js.map"
+    "build",
+    "typings"
   ],
   "typings": "./typings/index.d.ts",
   "types": "./typings/index.d.ts",