Update version code to submit APK without brand

Author: misaochan

commons/app/src/main/AndroidManifest.xml

@@ -1,6 +1,6 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="fr.free.nrw.commons"
-    android:versionCode="30"
+    android:versionCode="31"
     android:versionName="1.14" >
 
     <uses-sdk