No lookups in Gerrit's log4j2 message formatting

This is a safety net in case Gerrit or one of its plugins is using
log4j2 in unsafe ways.

Change-Id: I9d0a05fdad379a1e47f88cc6faa9425614f6515b

playbooks/roles/gerrit/templates/docker-compose.yaml.j2

@@ -33,6 +33,7 @@ services:
     environment:
       JAVA_OPTIONS: >-
         -Xlog:gc*:file=/var/gerrit/logs/jvm_gc.log:time,uptime,tid,level,tags:filecount=10,filesize=20M
+        -Dlog4j2.formatMsgNoLookups=true
 {% if gerrit_heap_limit is defined %}
         -Xmx{{ gerrit_heap_limit }}
 {% endif %}