transport.c::get_refs_via_curl(): do not leak refs_url

Signed-off-by: Mike Hommey <mh@glandium.org>
Signed-off-by: Tay Ray Chuan <rctay89@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/transport.c b/transport.c
index 89d846e..b7c1c39 100644
--- a/transport.c
+++ b/transport.c
@@ -519,6 +519,7 @@
 		free(ref);
 	}
 
+	free(refs_url);
 	return refs;
 }