Update package.json

Author: RivAl3x

package.json

@@ -8,7 +8,8 @@
     "start": "ng serve",
     "build": "ng build",
     "watch": "ng build --watch --configuration development",
-    "test": "ng test"
+    "test": "ng test",
+    "heroku-postbuild": "ng build"
 
 
   },