server incorrectly allows 0-RTT with reduced limits when using tls.Config.GetConfigForClient

[marten-seemann]

diff --git a/integrationtests/self/zero_rtt_test.go b/integrationtests/self/zero_rtt_test.go
index 46b3786dc..c77281bf9 100644
--- a/integrationtests/self/zero_rtt_test.go
+++ b/integrationtests/self/zero_rtt_test.go
@@ -817,7 +817,9 @@ var _ = Describe("0-RTT", func() {
                connIDLen := l
 
                It(fmt.Sprintf("correctly deals with 0-RTT rejections, for %d byte connection IDs", connIDLen), func() {
-                       tlsConf := getTLSConfig()
+                       tlsConf := &tls.Config{
+                               GetConfigForClient: func(*tls.ClientHelloInfo) (*tls.Config, error) { return getTLSConfig(), nil },
+                       }
                        clientConf := getTLSClientConfig()
                        dialAndReceiveSessionTicket(tlsConf, nil, clientConf)
                        // now dial new connection with different transport parameters