chore(bin/emqx): print env override when generating config

bin/emqx

@@ -230,7 +230,7 @@ generate_config() {
     ## ths command populates two files: app.<time>.config and vm.<time>.args
     ## disable SC2086 to allow EMQX_LICENSE_CONF_OPTION to split
     # shellcheck disable=SC2086
-    call_hocon -t "$NOW_TIME" -s emqx_schema -c "$RUNNER_ETC_DIR"/emqx.conf $EMQX_LICENSE_CONF_OPTION -d "$RUNNER_DATA_DIR"/configs generate
+    call_hocon -v -t "$NOW_TIME" -s emqx_schema -c "$RUNNER_ETC_DIR"/emqx.conf $EMQX_LICENSE_CONF_OPTION -d "$RUNNER_DATA_DIR"/configs generate
 
     ## filenames are per-hocon convention
     local CONF_FILE="$CONFIGS_DIR/app.$NOW_TIME.config"