Added a test case to verify user creation with service username
Added a test case to verify user creation with service username

     Verify Creating User With Service Username

Change-Id: I3e05db0fb7d9e7aaf897ceb7d0a182d379e627cb
Signed-off-by: manashsarma <bc095463df3ac81e71d6b05cdcfc30e87ec3c38e@in.ibm.com>

openbmc/openbmc-test-automation,openbmc/openbmc-test-automation