[monotouch-test] Ignore failing tests on Mac Catalyst/ARM64.

Ref: dotnet/runtime#55736

tests/monotouch-test/System.Net.Http/MessageHandlers.cs

@@ -88,6 +88,10 @@ public void DnsFailure (Type handlerType)
 		[Test]
 		public void TestNSUrlSessionHandlerCookies ()
 		{
+#if __MACCATALYST__
+			if (Runtime.IsARM64CallingConvention)
+				Assert.Ignore ("https://github.com/dotnet/runtime/issues/55736");
+#endif
 			var managedCookieResult = false;
 			var nativeCookieResult = false;
 			Exception ex = null;
@@ -133,6 +137,11 @@ public void TestNSUrlSessionHandlerCookies ()
 		[Test]
 		public void TestNSUrlSessionHandlerCookieContainer ()
 		{
+#if __MACCATALYST__
+			if (Runtime.IsARM64CallingConvention)
+				Assert.Ignore ("https://github.com/dotnet/runtime/issues/55736");
+#endif
+
 			var url = NetworkResources.Httpbin.CookiesUrl;
 			var cookie = new Cookie ("cookie", "chocolate-chip");
 			var cookieContainer = new CookieContainer ();
@@ -370,6 +379,11 @@ public void RejectSslCertificatesServicePointManager (Type handlerType)
 				Assert.Ignore ("Fails on macOS 10.10: https://github.com/xamarin/maccore/issues/1645");
 #endif
 
+#if __MACCATALYST__
+			if (Runtime.IsARM64CallingConvention)
+				Assert.Ignore ("https://github.com/dotnet/runtime/issues/55736");
+#endif
+
 			bool validationCbWasExecuted = false;
 			bool customValidationCbWasExecuted = false;
 			bool invalidServicePointManagerCbWasExcuted = false;