avoid read redundant string

Signed-off-by: Marcel Hibbe <dev@mhibbe.de>

app/src/main/java/com/nextcloud/talk/controllers/CallController.java

@@ -2363,11 +2363,9 @@ public class CallController extends BaseController {
     private String getDescriptionForCallType() {
         String appName = getResources().getString(R.string.nc_app_name);
         if (isVoiceOnlyCall){
-            return String.format(getResources().getString(R.string.nc_call_voice),
-                    getResources().getString(R.string.nc_app_name));
+            return String.format(getResources().getString(R.string.nc_call_voice), appName);
         } else {
-            return String.format(getResources().getString(R.string.nc_call_video),
-                    getResources().getString(R.string.nc_app_name));
+            return String.format(getResources().getString(R.string.nc_call_video), appName);
         }
     }