replace the GetLogWriter quic.Config option by a Tracer interface

interop/server/main.go

@@ -13,6 +13,7 @@ import (
 	"github.com/lucas-clemente/quic-go/internal/testdata"
 	"github.com/lucas-clemente/quic-go/interop/http09"
 	"github.com/lucas-clemente/quic-go/interop/utils"
+	"github.com/lucas-clemente/quic-go/qlog"
 )
 
 var tlsConf *tls.Config
@@ -44,8 +45,8 @@ func main() {
 	}
 	// a quic.Config that doesn't do a Retry
 	quicConf := &quic.Config{
-		AcceptToken:  func(_ net.Addr, _ *quic.Token) bool { return true },
-		GetLogWriter: getLogWriter,
+		AcceptToken: func(_ net.Addr, _ *quic.Token) bool { return true },
+		Tracer:      qlog.NewTracer(getLogWriter),
 	}
 	tlsConf = testdata.GetTLSConfig()
 	tlsConf.KeyLogWriter = keyLog