treewide: add final newline

pkgs/development/tools/build-managers/drake/gemset.nix

@@ -20,4 +20,4 @@
     };
     version = "0.9.2.0.3.1";
   };
-}
+}

pkgs/development/tools/build-managers/rake/gemset.nix

@@ -9,4 +9,4 @@
     };
     version = "12.3.2";
   };
-}
+}