tests: fix all leaks in surface-global-test

Fix all ASan reported leaks.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>

tests/surface-global-test.c

@@ -88,4 +88,7 @@ PLUGIN_TEST(surface_to_from_global)
 
 	weston_view_from_global(view, 5, 10, &ix, &iy);
 	assert(ix == 0 && iy == 0);
+
+	/* Destroys all views too. */
+	weston_surface_destroy(surface);
 }