[gnome-calendar] tests: Set TZ before running tests

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit f17c7b91b888ba9b8898abadeaadf12c8e26c4c2
Author: Georges Basile Stavracas Neto <georges stavracas gmail com>
Date:   Tue Jul 31 12:32:06 2018 -0300

    tests: Set TZ before running tests
    
    Otherwise, we're depending on the host machine to run
    the tests.

 tests/test-event.c | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/tests/test-event.c b/tests/test-event.c
index 956eab56..87b28e51 100644
--- a/tests/test-event.c
+++ b/tests/test-event.c
@@ -221,6 +221,8 @@ gint
 main (gint   argc,
       gchar *argv[])
 {
+  g_setenv ("TZ", "UTC", TRUE);
+
   g_test_init (&argc, &argv, NULL);
 
   g_test_add_func ("/event/new", event_new);