Actually remove the removed file from package.json.

Sigh :(
Signed-off-by: Katharine Berry <[email protected]>

Author: Katharine

app/package.json

@@ -464,11 +464,6 @@
           "name": "VIBE_STANDARD",
           "type": "raw"
         },
-        {
-          "file": "images/fence_pony.pdc",
-          "name": "FENCE_PONY",
-          "type": "raw"
-        },
         {
           "file": "images/fence_pony_color.png",
           "name": "FENCE_PONY_BITMAP",