Add loading for subscription stage

auth/src/main/res/layout/fragment_subscription_stage.xml

@@ -36,7 +36,7 @@
         app:layout_constraintVertical_bias="0.3"
         app:layout_constraintVertical_chainStyle="packed" />
 
-    <androidx.recyclerview.widget.RecyclerView
+    <org.futo.circles.core.view.LoadingRecyclerView
         android:id="@+id/rvSubscriptions"
         android:layout_width="0dp"
         android:layout_height="0dp"