[VOL-5177] - verify_voltha-openolt-adapter_sanity-test failure

vars/volthaStackDeploy.groovy
-----------------------------
  o Remove ONOS config loader fully deploy check.  Logic commented the check
    was only relevant to v2.8 and the adapter sanity test is timing out on it.
  o Refactor launchVolthaStack logic from process() into a named function
    for readability.  Use debug logic added for ONOS config loader to avoid
    pipeline problems and display command output periodically.
  o Changed sh "" calls into sh(label:'foo', script:'') to improve logging.
  o npm-groovy-lint cleanups:
    - braces on same line as function defs and try/catch/finally.
    - declare typed variables VS generic def.
    - single-quote strings that do not require variable expansion.

Change-Id: I7b6bbed459de1cc91e705cb598ade3297bfd6ec5
diff --git a/jjb/voltha-e2e/voltha-2.8.yaml b/jjb/voltha-e2e/voltha-2.8.yaml
index 994a79d..912e530 100644
--- a/jjb/voltha-e2e/voltha-2.8.yaml
+++ b/jjb/voltha-e2e/voltha-2.8.yaml
@@ -30,7 +30,7 @@
           code-branch: 'voltha-2.8'
           extraHelmFlags: '--set kafka.externalAccess.enabled=true,kafka.externalAccess.service.type=NodePort,kafka.externalAccess.service.nodePorts[0]=30201,kafka.externalAccess.service.domain=127.0.0.1'
           time-trigger: "H H/23 * * *"
-          logLevel: 'DEBUG'
+          logLevel: 'INFO'
           testTargets: |
             - target: voltha-pm-data-single-kind-att
               workflow: att