Removing typo for TT FailureScenario volt-add-subscriber-access command

Change-Id: Idd4cbb545869f43ef33fcd19638005e6d3c59169
diff --git a/tests/tt-workflow/Voltha_TT_FailureScenarios.robot b/tests/tt-workflow/Voltha_TT_FailureScenarios.robot
index 7009844..dc3ac9e 100755
--- a/tests/tt-workflow/Voltha_TT_FailureScenarios.robot
+++ b/tests/tt-workflow/Voltha_TT_FailureScenarios.robot
@@ -681,7 +681,7 @@
         ...    Catenate    volt-add-subscriber-unitag --tpId ${src['tp_id']} --sTag ${src['s_tag']}
         ...    --cTag ${src['c_tag']} ${src['onu']}-${src['uni_id']}
         ...    ELSE
-        ...    Set Variable    volt-add-subscriber-access ${of_id} ${onu_port}`
+        ...    Set Variable    volt-add-subscriber-access ${of_id} ${onu_port}
         Wait Until Keyword Succeeds    ${timeout}    2s    Execute ONOS CLI Command use single connection    ${ONOS_SSH_IP}
         ...    ${ONOS_SSH_PORT}    ${add_sub_cmd}
         Wait Until Keyword Succeeds    ${timeout}    5s