Skip operator user based on SKIP_OPERATOR_USER value

Changes:
    - Added a logic to skip operator user based on
      SKIP_OPERATOR_USER value

Tested:
    - Ran test_sessions_management.robot suite from sandbox

Signed-off-by: Rahul Maheshwari <rahulmaheshwari@in.ibm.com>
Change-Id: I033c7575f519bf6492ea2858876bfda48f55f838
diff --git a/redfish/service_root/test_sessions_management.robot b/redfish/service_root/test_sessions_management.robot
index 60a7514..718cb25 100644
--- a/redfish/service_root/test_sessions_management.robot
+++ b/redfish/service_root/test_sessions_management.robot
@@ -17,7 +17,9 @@
 
 @{ADMIN}       admin_user  TestPwd123
 @{OPERATOR}    operator_user  TestPwd123
-&{USERS}       Administrator=${ADMIN}  Operator=${OPERATOR}
+# User-driven input parameter to skip operator user.
+# -v SKIP_OPERATOR_USER:1  to skip from CLI.
+${SKIP_OPERATOR_USER}    ${0}
 
 
 *** Test Cases ***
@@ -275,6 +277,14 @@
     [Documentation]  Suite Setup Execution.
 
     Redfish.Login
+
+    # Skip operator user if SKIP_OPERATOR_USER is 1.
+    Run Keyword If
+    ...  ${SKIP_OPERATOR_USER} == ${1}
+    ...  Set Suite Variable  &{USERS}  Administrator=${ADMIN}
+    ...  ELSE
+    ...  Set Suite Variable  &{USERS}  Administrator=${ADMIN}  Operator=${OPERATOR}
+
     Create Users With Different Roles  users=${USERS}  force=${True}
     Get Default Timeout Value