fix(weapp): ping es6-promise at 4.2.3 to fix a wepy compile error

Author: leeyeh

package.json

@@ -28,7 +28,7 @@
   },
   "dependencies": {
     "debug": "^3.1.0",
-    "es6-promise": "^4.0.5",
+    "es6-promise": "4.2.3",
     "eventemitter3": "^2.0.3",
     "leancloud-realtime": "^4.0.0-beta.2",
     "leancloud-realtime-plugin-live-query": "^1.1.0",