Update POST request expectation response code

Changes:
     - By default, the HTTPS response code is 200 in the
       power on. Adding 204 response code expectations
       due to the latest bmcweb changes.

Tested:
     - Ran from sandbox.

Change-Id: I38b8e8e901a87eb1c9a1c38a2399b6ced0266514
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/lib/bmc_redfish_utils.robot b/lib/bmc_redfish_utils.robot
index 8d92755..a9ca187 100644
--- a/lib/bmc_redfish_utils.robot
+++ b/lib/bmc_redfish_utils.robot
@@ -35,6 +35,7 @@
     ${target}=  redfish_utils.Get Target Actions  /redfish/v1/Systems/system/  ComputerSystem.Reset
     ${payload}=  Create Dictionary  ResetType=${reset_type}
     ${resp}=  Redfish.Post  ${target}  body=&{payload}
+    ...  valid_status_codes=[${HTTP_OK}, ${HTTP_NO_CONTENT}]
 
 
 Redfish BMC Reset Operation