update domain name to os.mbed.com

Author: studavekar

features/FEATURE_LWIP/TESTS/mbedmicro-net/tcp_hello_world/main.cpp

@@ -33,7 +33,7 @@ using namespace utest::v1;
 
 namespace {
     // Test connection information
-    const char *HTTP_SERVER_NAME = "developer.mbed.org";
+    const char *HTTP_SERVER_NAME = "os.mbed.com";
     const char *HTTP_SERVER_FILE_PATH = "/media/uploads/mbed_official/hello.txt";
     const int HTTP_SERVER_PORT = 80;
 #if defined(TARGET_VK_RZ_A1H)