ostree_repo_pull_from_remotes_async: Fix leak of options

copy_option() unnecessarily passed ownership of the value
to g_variant_dict_insert_value, but that already refs, so it was leaked.

Closes: #1702
Approved by: cgwalters

src/libostree/ostree-repo-pull.c

@@ -5667,7 +5667,7 @@ copy_option (GVariantDict       *master_options,
 {
   g_autoptr(GVariant) option_v = g_variant_dict_lookup_value (master_options, key, expected_type);
   if (option_v != NULL)
-    g_variant_dict_insert_value (slave_options, key, g_steal_pointer (&option_v));
+    g_variant_dict_insert_value (slave_options, key, option_v);
 }
 
 /**