Fix user deletion with new notifications_deliveries table for real (#4473)

Maybe this will work? I dunno but users are still saying they're getting errors deleting accs. In theory it shouldn't matter if the transaction all gets committed at the same time, though, right? I can't really test this so I would like someone to tell me whether this will actually make a difference.

Co-authored-by: François-X. T <fetch@ferrous.ch>

apps/labrinth/src/database/models/user_item.rs

@@ -559,16 +559,6 @@ impl DBUser {
             .try_collect::<Vec<i64>>()
             .await?;
 
-            sqlx::query!(
-                "
-                DELETE FROM notifications
-                WHERE user_id = $1
-                ",
-                id as DBUserId,
-            )
-            .execute(&mut **transaction)
-            .await?;
-
             sqlx::query!(
                 "
                 DELETE FROM notifications_actions
@@ -589,6 +579,16 @@ impl DBUser {
             .execute(&mut **transaction)
             .await?;
 
+            sqlx::query!(
+                "
+                DELETE FROM notifications
+                WHERE user_id = $1
+                ",
+                id as DBUserId,
+            )
+            .execute(&mut **transaction)
+            .await?;
+
             let user_collections = sqlx::query!(
                 "
                 SELECT id