hopefully fix the bug preventing post deletions sometimes.

database/postgres/posts.go

@@ -253,6 +253,11 @@ func (r *postRepository) Delete(ctx context.Context, post models.Post) error {
 		return err
 	}
 
+	err = q.MovePost(ctx, psqlcore.MovePostParams{ID: post.ID, Position: -1})
+	if err != nil {
+		return err
+	}
+
 	err = q.DeletePost(ctx, post.ID)
 	if err != nil {
 		return err