[gimp] add to fix test link on OSX

[Alex Samorukov <asamorukov src gnome org>]

commit 53f0f935567965db01769c0c53375299c27f0089
Author: Alex Samorukov <samm os2 kiev ua>
Date:   Fri Nov 23 10:45:39 2018 +0100

    add  to fix test link on OSX
    
    (cherry picked from commit d650e9f81f3362ce4e93af10f334d49c2a354d03)

 app/tests/Makefile.am | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/app/tests/Makefile.am b/app/tests/Makefile.am
index 3b6076f7c4..81e1f5608d 100644
--- a/app/tests/Makefile.am
+++ b/app/tests/Makefile.am
@@ -125,6 +125,7 @@ LDADD = \
        $(GIMPICONRC)                                                   \
        $(GTK_LIBS)                                                     \
        $(APPSTREAM_GLIB_LIBS)                                          \
+       $(GTK_MAC_INTEGRATION_LIBS)                                     \
        $(DBUS_GLIB_LIBS)                                               \
        $(GDK_PIXBUF_LIBS)                                              \
        $(FREETYPE_LIBS)                                                \