Redfish update test suite Force tags as per standard

Changes:
   - Update Tags names for the test suite

Note: Refer CONTRIBUTING.md for under Tags section
      documentation.

Tested:
   - NA

Change-Id: Ice5fa1a185876774d9e9bce4ff53f834b2a1f652
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/redfish/managers/test_certificate.robot b/redfish/managers/test_certificate.robot
index e7e70d1..e71a33a 100644
--- a/redfish/managers/test_certificate.robot
+++ b/redfish/managers/test_certificate.robot
@@ -7,7 +7,7 @@
 Resource         ../../lib/certificate_utils.robot
 Library          String
 
-Force Tags       Certificate_Test
+Force Tags       Certificate
 
 Suite Setup      Suite Setup Execution
 Suite Teardown   Suite Teardown