Switch from Force Tags to Test Tags

Force Tags is deprecated in Robot 7.0 and will eventually
warn and then after that stop working. Test Tags performs
the same function per docs.

Change-Id: I7cf305754b247b995a05d8da3b9de9ed613ecae2
Signed-off-by: Matt Fischer <matthew.fischer@hpe.com>
diff --git a/redfish/events/test_bmc_snmp_trap.robot b/redfish/events/test_bmc_snmp_trap.robot
index d7d7854..6168673 100644
--- a/redfish/events/test_bmc_snmp_trap.robot
+++ b/redfish/events/test_bmc_snmp_trap.robot
@@ -15,7 +15,7 @@
 Suite Setup       Suite Setup Execution
 Suite Teardown    Suite Teardown Execution
 
-Force Tags        BMC_SNMP_Trap
+Test Tags        BMC_SNMP_Trap
 
 *** Test Cases ***