[Conf] Add missing includes

conf/modules.d/external_services.conf

     # `whitelist` points to a map of IP addresses. Mail from these addresses is not scanned.
     whitelist = "/etc/rspamd/antivirus.wl";
   }
+
+  .include(try=true,priority=5) "${DBDIR}/dynamic/external_services.conf"
+  .include(try=true,priority=1,duplicate=merge) "$LOCAL_CONFDIR/local.d/external_services.conf"
+  .include(try=true,priority=10) "$LOCAL_CONFDIR/override.d/external_services.conf"
 }

src/plugins/lua/external_services.lua

     end
   end
 
+  rspamd_logger.infox(rspamd_config, 'registered external services rule: %s',
+      rule.name)
+
   return scan_cb, rule
 end