[libgfbgraph] tests/gtestutils: Replace unused attribute with G_GNUC_UNUSED macro

[Leesoo Ahn <yisooan src gnome org>]

commit 76fec04362bd7ddaf4e77aeb2571dbaaaa9ddd40
Author: Leesoo Ahn <yisooan fedoraproject org>
Date:   Tue May 21 13:10:37 2019 +0900

    tests/gtestutils: Replace unused attribute with G_GNUC_UNUSED macro
    
    The macro will do nothing if a compiler doesn't support the GNU
    compiler extension instead of raising an error.

 tests/gtestutils.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/tests/gtestutils.c b/tests/gtestutils.c
index af76870..7fd8d78 100644
--- a/tests/gtestutils.c
+++ b/tests/gtestutils.c
@@ -174,7 +174,7 @@ gfbgraph_test_fixture_setup (GFBGraphTestFixture *fixture, gconstpointer user_da
 }
 
 static void
-gfbgraph_test_fixture_teardown (GFBGraphTestFixture *fixture, __attribute__ ((unused)) gconstpointer 
user_data)
+gfbgraph_test_fixture_teardown (GFBGraphTestFixture *fixture, G_GNUC_UNUSED gconstpointer user_data)
 {
         SoupSession *ssession;
         SoupMessage *smessage;
@@ -199,7 +199,7 @@ gfbgraph_test_fixture_teardown (GFBGraphTestFixture *fixture, __attribute__ ((un
 }
 
 static void
-gfbgraph_test_me (GFBGraphTestFixture *fixture, __attribute__ ((unused)) gconstpointer user_data)
+gfbgraph_test_me (GFBGraphTestFixture *fixture, G_GNUC_UNUSED gconstpointer user_data)
 {
         GFBGraphUser *me;
         GError *error = NULL;
@@ -216,7 +216,7 @@ gfbgraph_test_me (GFBGraphTestFixture *fixture, __attribute__ ((unused)) gconstp
 }
 
 static void
-gfbgraph_test_album (GFBGraphTestFixture *fixture, __attribute__ ((unused)) gconstpointer user_data)
+gfbgraph_test_album (GFBGraphTestFixture *fixture, G_GNUC_UNUSED gconstpointer user_data)
 {
         GFBGraphUser *me;
         GFBGraphAlbum *album;