Fix typo

Author: szg251

flake.nix

@@ -42,7 +42,7 @@
     };
 
     blockfrost.follows = "cardano-nix/blockfrost";
-    db-sync.follows = "cardano-nir/cardano-db-sync";
+    db-sync.follows = "cardano-nix/cardano-db-sync";
 
     hercules-ci-effects.url = "github:hercules-ci/hercules-ci-effects";
   };