Make default user auth insecure again.

services/clickhouse.hcl

@@ -25,6 +25,11 @@ job "clickhouse" {
         ports = [ "clickhouse" ]
       }
 
+      env {
+        # TODO: this is insecure, see "Managing default user" at https://hub.docker.com/r/clickhouse/clickhouse-server/
+        CLICKHOUSE_SKIP_USER_SETUP = 1
+      }
+
       service {
         name = "clickhouse"
         port = "clickhouse"