Provide access to underlying quic socket

Summary: This diff provides access to the underlying socket in a quic network transport, which is used to update the network simulator configuration in a subsequent diff in this stack.

Reviewed By: kvtsoy

Differential Revision: D64691098

fbshipit-source-id: 349ee58038d232a8a454fa73e630872a26e73227

quic/api/QuicTransportBase.h

@@ -300,6 +300,10 @@ class QuicTransportBase : public QuicSocket,
     return conn_->retransmissionPolicies;
   }
 
+  [[nodiscard]] QuicAsyncUDPSocket* getUdpSocket() const {
+    return socket_.get();
+  }
+
  protected:
   void processCallbacksAfterNetworkData();
   void invokeStreamsAvailableCallbacks();