fix(syncforreddit/change-oauth-client-id): use downloads directory

This fixes permission errors on Android

dummy/src/main/java/android/os/Environment.java

@@ -3,7 +3,9 @@ package android.os;
 import java.io.File;
 
 public final class Environment {
-    public static File getExternalStorageDirectory() {
+    public static String DIRECTORY_DOWNLOADS = "Download";
+
+    public static File getExternalStoragePublicDirectory(final String type) {
         throw new UnsupportedOperationException("Stub");
     }
 }