fix(server): Execute query in AlbumRepository.removeAsset method (#6216)

The current `removeAsset` implementation just builds the query but does
not execute it. That also seems to be the reason the `@GenerateSql`
decorator was commented out.

server/src/infra/sql/album.repository.sql

@@ -508,6 +508,11 @@ FROM
 WHERE
   "AlbumEntity"."deletedAt" IS NULL
 
+-- AlbumRepository.removeAsset
+DELETE FROM "albums_assets_assets"
+WHERE
+  "albums_assets_assets"."assetsId" = $1
+
 -- AlbumRepository.removeAssets
 DELETE FROM "albums_assets_assets"
 WHERE