update mtu in quic

vendor/github.com/lucas-clemente/quic-go/internal/protocol/protocol.go

@@ -65,7 +65,7 @@ type ApplicationErrorCode uint16
 // ethernet's max size, minus the IP and UDP headers. IPv6 has a 40 byte header,
 // UDP adds an additional 8 bytes.  This is a total overhead of 48 bytes.
 // Ethernet's max packet size is 1500 bytes,  1500 - 48 = 1452.
-const MaxReceivePacketSize ByteCount = 1452
+const MaxReceivePacketSize ByteCount = 1452 - 32
 
 // DefaultTCPMSS is the default maximum packet size used in the Linux TCP implementation.
 // Used in QUIC for congestion window computations in bytes.