fix: demo/turnkey/web_audio里面的mqtt链接不应该有ca_file变量

script/turnkey/web_audio/main.lua

@@ -92,7 +92,7 @@ sys.taskInit(function()
     if not result then
         log.info("网络连接失败")
     end
-    mqttc = mqtt.create(nil, mqtt_host, mqtt_port, mqtt_isssl, ca_file)
+    mqttc = mqtt.create(nil, mqtt_host, mqtt_port, mqtt_isssl)
     mqttc:auth(client_id, user_name, password) -- client_id必填,其余选填
     mqttc:keepalive(30) -- 默认值240s
     mqttc:autoreconn(true, 3000) -- 自动重连机制