[VOL-4041] Migration to single ONOS SSH connection

Change-Id: I91f5f3c96585097486bc862118d8753bf4b30cba
diff --git a/tests/software-upgrades/Voltha_ComponentsUpgrade.robot b/tests/software-upgrades/Voltha_ComponentsUpgrade.robot
index 30016a7..c3ef8aa 100755
--- a/tests/software-upgrades/Voltha_ComponentsUpgrade.robot
+++ b/tests/software-upgrades/Voltha_ComponentsUpgrade.robot
@@ -123,6 +123,7 @@
 Teardown Suite
     [Documentation]    Tear down steps for the suite
     Run Keyword If    ${has_dataplane}    Clean Up Linux
+    Close All ONOS SSH Connections
 
 Create Voltha Comp Under Test List
     [Documentation]    Creates a list of Voltha Components to Test from the input variable string