Try fix Element not found bug

src/app/rules/rules.component.spec.ts

-import { ComponentFixture, TestBed } from '@angular/core/testing';
-
+import { async, ComponentFixture, TestBed } from '@angular/core/testing';
+import { CUSTOM_ELEMENTS_SCHEMA, NO_ERRORS_SCHEMA } from '@angular/core';
 import { RulesComponent } from './rules.component';
 
+
 describe('RulesComponent', () => {
   let component: RulesComponent;
   let fixture: ComponentFixture<RulesComponent>;
 
+  beforeEach(async(() => {
+    TestBed.configureTestingModule({
+      declarations: [ RulesComponent ],
+      schemas: [CUSTOM_ELEMENTS_SCHEMA, NO_ERRORS_SCHEMA]
+    }).compileComponents();
+  }));
+
   beforeEach(async () => {
     await TestBed.configureTestingModule({
       declarations: [ RulesComponent ]