Add Object.freeze on private enums

Improve code readability

src/systemData/inspectionDecision.js

@@ -1,9 +1,9 @@
-var InspectionDecision = {
+var InspectionDecision = Object.freeze({
   DoNothing: 'doNothing',
   EndOperation: 'endOperation',
   Retry: 'retry',
   Reconnect: 'reconnect',
   Subscribed: 'subscribed'
-};
+});
 
 module.exports = InspectionDecision;