Update offboard-machine-api.md

Author: denisebmsft

defender-endpoint/api/offboard-machine-api.md

@@ -99,7 +99,7 @@ If successful, this method returns `200 - Created response` code and [Machine Ac
 
 ### Request
 
-Here's an example of the request. If there's no JSON comment added, it errors out with code **400**.
+Here's an example of the request. If there's no JSON comment added, it errors out with code `400`.
 
 ```http
 POST https://api.security.microsoft.com/api/machines/1e5bc9d7e413ddd7902c2932e418702b84d0cc07/offboard