Revert "Temporary fix for connection with greengrass china endpoint"

This reverts commit 88fc959.

Author: jmklix

discovery/source/DiscoveryClient.cpp

@@ -31,12 +31,6 @@ namespace Aws
             Crt::StringStream ss;
             ss << "greengrass-ats.iot." << clientConfig.Region << ".amazonaws.com";
 
-            // Temporary fix for connection with china endpoint
-            if (clientConfig.Region == "cn-north-1")
-            {
-                ss << ".cn";
-            }
-
             Crt::Io::TlsConnectionOptions tlsConnectionOptions = clientConfig.TlsContext->NewConnectionOptions();
             uint16_t port = 443;