Tests/datetime: set the weekday to avoid Exactness error

The weekday, if not set, is the weekday of the day the test is run (i.e
today).
It means Exactness shots will be different most of the time.

src/bin/elementary/test_datetime.c

@@ -22,6 +22,7 @@ _bt_clicked(void *data EINA_UNUSED, Evas_Object *obj, void *event_info EINA_UNUS
    t = time(NULL);
    localtime_r(&t, &new_time);
 
+   new_time.tm_wday = 6;
    new_time.tm_year = 85;
    new_time.tm_mon = 9;
    new_time.tm_mday = 26;