Fix not being able to deal with uints from subscribers

Description

Related Issue

Motivation and Context

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

controller/nucleus/networkElementWatcher.go

@@ -245,7 +245,17 @@ func (n *NetworkElementWatcher) handleSubscribeResponseUpdate(resp *gpb.Subscrib
 			log.Errorf("Error trying to create a string from path: %v", err)
 		}
 
-		pathsAndValues[pathString] = update.Val.GetStringVal()
+		switch v := update.GetVal().GetValue().(type) {
+		case *gpb.TypedValue_StringVal:
+			pathsAndValues[pathString] = update.Val.GetStringVal()
+		case *gpb.TypedValue_JsonIetfVal:
+			pathsAndValues[pathString] = string(update.GetVal().GetJsonIetfVal())
+		case *gpb.TypedValue_UintVal:
+			pathsAndValues[pathString] = fmt.Sprintf("%d", update.Val.GetUintVal())
+		default:
+			log.Errorf("The given value of type: %T, provided by a SubResponse from network element with ID: %s is not supported", v, subscriptionInfo.NetworkElementID)
+			return
+		}
 	}
 
 	mneID, err := uuid.Parse(subscriptionInfo.NetworkElementID)