Fixed Exec Pod In Kube keyword to return first pod instance

Change-Id: I637992ff841cbb555298baa8f28cf467c1d1d647
diff --git a/libraries/k8s.robot b/libraries/k8s.robot
index 38da3ee..d656dfd 100755
--- a/libraries/k8s.robot
+++ b/libraries/k8s.robot
@@ -70,7 +70,8 @@
     [Arguments]    ${namespace}    ${name}    ${command}    ${grep}=${EMPTY}
     [Documentation]    Uses kubectl to execute a command in the pod and return the output
     ${rc}    ${exec_pod_name}=    Run Keyword If     '${grep}'=='${EMPTY}'
-    ...    Run and Return Rc and Output    kubectl -n ${namespace} get pods -l app.kubernetes.io/name=${name} -o name
+    ...    Run and Return Rc and Output
+    ...    kubectl -n ${namespace} get pods -l app.kubernetes.io/name=${name} -o name | awk 'NR==1{print $1}'
     ...    ELSE    Run and Return Rc and Output
     ...    kubectl -n ${namespace} get pods -l app.kubernetes.io/name=${name} -o name \| grep ${grep}
     Log    ${exec_pod_name}