Unified code style (#2137)

src/Rtp/RtpSender.h

@@ -22,7 +22,7 @@ namespace mediakit{
 //rtp发送客户端，支持发送GB28181协议
 class RtpSender final : public MediaSinkInterface, public std::enable_shared_from_this<RtpSender>{
 public:
-    typedef std::shared_ptr<RtpSender> Ptr;
+    using Ptr = std::shared_ptr<RtpSender>;
 
     RtpSender(toolkit::EventPoller::Ptr poller = nullptr);
     ~RtpSender() override;