REFACTOR - remove _.debounce and _.isEqual

Lodash is being removed from core Discourse.

assets/javascripts/discourse/mixins/undo-changes.js.es6

@@ -3,6 +3,7 @@ import { default as wizardSchema } from '../lib/wizard-schema';
 import { set, get } from "@ember/object";
 import Mixin from "@ember/object/mixin";
 import { observes } from 'discourse-common/utils/decorators';
+import { deepEqual } from 'discourse-common/lib/object';
 
 export default Mixin.create({
   didInsertElement() {
@@ -90,7 +91,7 @@ export default Mixin.create({
   toggleUndo() {
     const current = this.get(this.componentType);
     const original = this.originalObject;
-    this.set('showUndo', !_.isEqual(current, original));
+    this.set('showUndo', !deepEqual(current, original));
   },
 
   actions: {

assets/javascripts/wizard/lib/user-search.js.es6

@@ -1,5 +1,6 @@
 import { CANCELLED_STATUS } from 'discourse/lib/autocomplete';
 import getUrl from 'discourse-common/lib/get-url';
+import discourseDebounce from "discourse/lib/debounce";
 
 var cache = {},
     cacheTopicId,
@@ -39,7 +40,7 @@ function performSearch(term, topicId, includeGroups, includeMentionableGroups, i
   });
 }
 
-var debouncedSearch = _.debounce(performSearch, 300);
+var debouncedSearch = discourseDebounce(performSearch, 300);
 
 function organizeResults(r, options) {
   if (r === CANCELLED_STATUS) { return r; }