Expose LOG_MAX_AGE

Reviewed-on: coop-cloud/traefik#55
Reviewed-by: decentral1se <decentral1se@noreply.git.coopcloud.tech>

.env.sample

@@ -10,6 +10,7 @@ LETS_ENCRYPT_EMAIL=certs@example.com
 # DASHBOARD_ENABLED=true
 # WARN, INFO etc.
 LOG_LEVEL=WARN
+LOG_MAX_AGE=1
 
 # This is here so later lines can extend it; you likely don't wanna edit
 COMPOSE_FILE="compose.yml"