Always schedule next ephemeral task after message deletion

If no messages were deleted, it means the task was scheduled earlier
then needed and should be rescheduled.

src/ephemeral.rs

@@ -321,9 +321,7 @@ pub(crate) async fn delete_expired_messages(context: &Context) -> Result<bool, E
         updated |= rows_modified > 0;
     }
 
-    if updated {
-        schedule_ephemeral_task(context).await;
-    }
+    schedule_ephemeral_task(context).await;
     Ok(updated)
 }