polling for deletion of subscriber at teardown

Change-Id: I5344fac37e2ae09359f4db09f84d5de67107339d
diff --git a/src/test/cord-api/Tests/WorkflowValidations/ATT_Test001.robot b/src/test/cord-api/Tests/WorkflowValidations/ATT_Test001.robot
index eb2e246..9ad9a48 100644
--- a/src/test/cord-api/Tests/WorkflowValidations/ATT_Test001.robot
+++ b/src/test/cord-api/Tests/WorkflowValidations/ATT_Test001.robot
@@ -388,6 +388,7 @@
     Wait Until Keyword Succeeds    60s    2s    Clean Up Objects    ${VOLT_SUBSCRIBER}
     Wait Until Keyword Succeeds    60s    2s    Clean Up Objects    ${ATT_WHITELIST}
     Wait Until Keyword Succeeds    60s    2s    Clean Up Objects    ${ATT_SERVICEINSTANCES}
+    Validate Subscriber Count    30s    2s    Validate Subscriber Count    0
     Sleep    10s
     Wait Until Keyword Succeeds    60s    2s    Clean Up Objects    ${VOLT_DEVICE}
     Wait Until Keyword Succeeds    120s    10s    Check Remote System Reachability    False    ${olt_ip}