fix: make di compat property non-enumerable

lib/util/CompatibilityUtil.js

@@ -65,6 +65,7 @@ export function ensureCompatDiRef(businessObject) {
   // bpmnElement can have multiple independent DIs
   if (!has(businessObject, 'di')) {
     Object.defineProperty(businessObject, 'di', {
+      enumerable: false,
       get: function() {
         throw new Error(DI_ERROR_MESSAGE);
       }