Update use of internal hostname in LSO callback URLs

gso/services/lso_client.py

@@ -37,7 +37,7 @@ def _send_request(parameters: dict, callback_route: str) -> None:
     params = oss.PROVISIONING_PROXY
 
     # Build up a callback URL of the Provisioning Proxy to return its results to.
-    callback_url = f"{oss.GENERAL.public_hostname}{callback_route}"
+    callback_url = f"{oss.GENERAL.internal_hostname}{callback_route}"
     debug_msg = f"[provisioning proxy] Callback URL set to {callback_url}"
     logger.debug(debug_msg)