Fix test docker readiness check

 - add probe_test_docker function to check test docker readiness
 - minor improvements to docker_run and test docker startup scripts

Issue-ID: SDC-2376
Change-Id: If1ee25e8c7850c8e65a520f645ff80c7d5d36373
Signed-off-by: kaihlavi <l.kaihlavirt@partner.samsung.com>
diff --git a/ui-ci/sdc-ui-tests/startup.sh b/ui-ci/sdc-ui-tests/startup.sh
index 4700e68..9078980 100644
--- a/ui-ci/sdc-ui-tests/startup.sh
+++ b/ui-ci/sdc-ui-tests/startup.sh
@@ -8,9 +8,12 @@
 rc=$?
 
 if [[ $rc != 0 ]]; then
-   echo "Sanity failed !!!"
+   echo "Startup failed !!!"
    exit $rc
 else
-   echo "completed successfully :-)"
-#   exit 0
+# Note that the output below is monitored in CSIT by
+# sdc/sdc-os-chef/scripts/docker_run.sh
+# If this text is changed, docker_run.sh check for sdc-ui-tests docker
+# startup must be adjusted accordingly!
+   echo "Startup completed successfully"
 fi