Disable SSLClientSocketTest.TLS13DowngradeEnforced on macOS

This test is failing on macOS build bots due to its long log output.

TBR=davidben@chromium.org

Bug: 1017036
Change-Id: I69d0181f71bf1c5791d566a84685efadecad6bd2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1875351Reviewed-by: Hajime Hoshi <hajimehoshi@chromium.org>
Commit-Queue: Hajime Hoshi <hajimehoshi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#708530}

net/socket/ssl_client_socket_unittest.cc

@@ -5364,7 +5364,13 @@ TEST_F(SSLClientSocketTest, Tag) {
 }
 
 // Test downgrade enforcement behaves as expected.
-TEST_F(SSLClientSocketTest, TLS13DowngradeEnforced) {
+// Failed on macOS. See https://crbug.com/1017036
+#if defined(OS_MACOSX)
+#define MAYBE_TLS13DowngradeEnforced DISABLED_TLS13DowngradeEnforced
+#else
+#define MAYBE_TLS13DowngradeEnforced TLS13DowngradeEnforced
+#endif
+TEST_F(SSLClientSocketTest, MAYBE_TLS13DowngradeEnforced) {
   for (auto tls_max_version :
        {SpawnedTestServer::SSLOptions::TLS_MAX_VERSION_TLS1_0,
         SpawnedTestServer::SSLOptions::TLS_MAX_VERSION_TLS1_1,