use single ssh connection to onos
It belongs to VOL-4041 and is the second part.
Keyword 'Execute ONOS CLI Command on open connection' is deprecated
and is replaced by keyword
'Execute ONOS CLI Command use single connection' for all test suites
and libraries.

Change-Id: Ib5078b50d22e812e927e437a0e6f0e249f95ee9a
diff --git a/tests/openonu-go-adapter/Voltha_ONUTemplateTests.robot b/tests/openonu-go-adapter/Voltha_ONUTemplateTests.robot
index 1c5b1ac..3b86bbc 100755
--- a/tests/openonu-go-adapter/Voltha_ONUTemplateTests.robot
+++ b/tests/openonu-go-adapter/Voltha_ONUTemplateTests.robot
@@ -89,8 +89,6 @@
     ...    debugmode:${debugmode}, logging:${logging}, pausebeforecleanup:${pausebeforecleanup},
     Log    ${LogInfo}    console=yes
     Common Test Suite Setup
-    ${onos_ssh_connection}    Open ONOS SSH Connection    ${ONOS_SSH_IP}    ${ONOS_SSH_PORT}
-    Set Suite Variable  ${onos_ssh_connection}
     # delete etcd MIB Template Data
     Delete MIB Template Data
 
@@ -102,7 +100,7 @@
     Run Keyword If    ${pausebeforecleanup}    Pause Execution    Press OK to continue with clean up!
     Run Keyword If    ${pausebeforecleanup}    Log    Teardown will be continued...    console=yes
     Run Keyword If    ${teardown_device}    Delete All Devices and Verify
-    Wait for Ports in ONOS for all OLTs      ${onos_ssh_connection}  0   BBSM
+    Wait for Ports in ONOS for all OLTs      ${ONOS_SSH_IP}    ${ONOS_SSH_PORT}  0   BBSM
     # delete etcd MIB Template Data (for repeating test)
     Delete MIB Template Data
     Close All ONOS SSH Connections