Corrected method of HTTPS certificate upload

For HTTPS certificate only replace is possible so replaced install certificate with replace certificate

Change-Id: I1e3f3e703f591700855bf24456b1487b4a92fb30
Signed-off-by: Ashwini Chandrappa <Ashwini.Chandrappa777@ibm.com>
diff --git a/gui/gui_test/access_control_menu/test_ssl_certificates_sub_menu.robot b/gui/gui_test/access_control_menu/test_ssl_certificates_sub_menu.robot
index 2ba9186..10e6947 100644
--- a/gui/gui_test/access_control_menu/test_ssl_certificates_sub_menu.robot
+++ b/gui/gui_test/access_control_menu/test_ssl_certificates_sub_menu.robot
@@ -95,9 +95,8 @@
     [Documentation]  Install HTTPS certificate via Redfish and verify it in GUI.
     [Tags]  Verify_Installed_HTTPS_Certificate
 
-    # Install HTTPS certificate.
-    ${file_data}=  Generate Certificate File Data  Server
-    Install Certificate File On BMC  ${REDFISH_HTTPS_CERTIFICATE_URI}  ok  data=${file_data}
+    # Replace HTTPS certificate.
+    Replace Certificate Via Redfish  Server   Valid Certificate Valid Privatekey  ok
 
     # Verify certificate is available in GUI.
     Wait Until Page Contains  HTTPS Certificate  timeout=10