minor fixes.

Author: zhuizhuhaomeng

src/ngx_http_lua_util.c

@@ -1468,6 +1468,7 @@ ngx_http_lua_run_thread(lua_State *L, ngx_http_request_t *r,
 
                 if (ctx->cur_co_ctx->is_uthread
                     && ctx->cur_co_ctx->co_ref != LUA_NOREF)
+                {
                     ngx_http_lua_del_thread(r, L, ctx, ctx->cur_co_ctx);
                     ctx->uthreads--;
                 }