advancedtls: use realistic ciphersuite in test (#7273)

Instead of 3DES, something which should basically never be used in
production. Go is removing default support for 3DES is Go 1.24,
requiring new modules to opt into support for this cipher.

security/advancedtls/advancedtls_test.go

@@ -1107,7 +1107,7 @@ func (s) TestGetCertificatesSNI(t *testing.T) {
 			}
 			pointFormatUncompressed := uint8(0)
 			clientHello := &tls.ClientHelloInfo{
-				CipherSuites:      []uint16{tls.TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA},
+				CipherSuites:      []uint16{tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA},
 				ServerName:        test.serverName,
 				SupportedCurves:   []tls.CurveID{tls.CurveP256},
 				SupportedPoints:   []uint8{pointFormatUncompressed},