Fix http_req sample bug
diff --git a/samplecode/http_req/app/src/main.rs b/samplecode/http_req/app/src/main.rs
index f69e304..3a84949 100644
--- a/samplecode/http_req/app/src/main.rs
+++ b/samplecode/http_req/app/src/main.rs
@@ -60,7 +60,7 @@
 
     let mut retval = sgx_status_t::SGX_SUCCESS;
 
-    let hostname = "example.com";
+    let hostname = "www.rust-lang.org";
     let port = 443;
 
     let hostname = format!("https://{}:{}", hostname, port);