Add TZ to mailu.env

setup/flavors/compose/mailu.env

@@ -42,6 +42,9 @@ AUTH_RATELIMIT_USER={{ auth_ratelimit_user }}/day
 # Opt-out of statistics, replace with "True" to opt out
 DISABLE_STATISTICS={{ disable_statistics or 'False' }}
 
+# Timezone for the Mailu containers. See this link for all possible values https://en.wikipedia.org/wiki/List_of_tz_database_time_zones
+TZ=Etc/UTC
+
 ###################################
 # Optional features
 ###################################