rename icon.png to logo.png

CloudronManifest.json

@@ -23,7 +23,7 @@
   "manifestVersion": 1,
   "website": "https://gogs.io",
   "contactEmail": "apps@cloudron.io",
-  "icon": "gogs-lg.png",
+  "icon": "file://logo.png",
   "mediaLinks": [
     "https://gogs.io/img/screenshots/1.png",
     "https://gogs.io/img/screenshots/2.png",