feat(nx): upgrade nx 20 and angular 19

apps/testing/24-harness-creation/src/app/app.component.ts

@@ -2,7 +2,6 @@ import { Component, signal } from '@angular/core';
 import { SliderComponent } from './slider.component';
 
 @Component({
-  standalone: true,
   imports: [SliderComponent],
   selector: 'app-root',
   template: `

apps/testing/24-harness-creation/src/app/slider.component.ts

@@ -48,7 +48,6 @@ import { skip } from 'rxjs';
       }
     `,
   ],
-  standalone: true,
   imports: [MatCardModule, MatSliderModule, MatIconModule, FormsModule],
 })
 export class SliderComponent implements OnInit {

apps/testing/24-harness-creation/src/styles.scss

@@ -7,7 +7,8 @@
 
 /* You can add global styles to this file, and also import other style files */
 
-@include mat.core();
+@include mat.elevation-classes();
+@include mat.app-background();
 
 $theme-primary: mat.m2-define-palette(mat.$m2-indigo-palette);
 $theme-accent: mat.m2-define-palette(mat.$m2-pink-palette, A200, A100, A400);