Update redfish rsp code for cert update/install

Changes:
    - Updated redfish response code to expect either 200 or 204
      while updating or installing certificate via redfish.
    - Both client / server certificate response code updated.

Tested:
     - Ran All The Scripts Successfully

Change-Id: Iae3c9c68b433e78c7c51a8891c0df1ac084b8595
Signed-off-by: ganesanb <ganesanb@ami.com>
diff --git a/lib/certificate_utils.robot b/lib/certificate_utils.robot
index 60dcb27..e8faf5d 100755
--- a/lib/certificate_utils.robot
+++ b/lib/certificate_utils.robot
@@ -235,7 +235,7 @@
     ${payload}=  Create Dictionary  CertificateString=${file_data}
     ...  CertificateType=PEM  CertificateUri=${certificate_dict}
 
-    ${expected_resp}=  Set Variable If  '${expected_status}' == 'ok'  ${HTTP_OK}
+    ${expected_resp}=  Set Variable If  '${expected_status}' == 'ok'  ${HTTP_OK}, ${HTTP_NO_CONTENT}
     ...  '${expected_status}' == 'error'  ${HTTP_NOT_FOUND}, ${HTTP_INTERNAL_SERVER_ERROR}
     ${resp}=  redfish.Post  /redfish/v1/CertificateService/Actions/CertificateService.ReplaceCertificate
     ...  body=${payload}  valid_status_codes=[${expected_resp}]