TUN-5590: QUIC datagram max user payload is 1217 bytes

datagramsession/transport.go

@@ -8,6 +8,6 @@ type transport interface {
 	SendTo(sessionID uuid.UUID, payload []byte) error
 	// ReceiveFrom reads the next datagram from the transport
 	ReceiveFrom() (uuid.UUID, []byte, error)
-	// Max transmission unit of the transport
-	MTU() uint
+	// Max transmission unit to receive from the transport
+	ReceiveMTU() uint
 }