[PM-2871] Submenu UI elements cannot be accessed by keyboard navigation when screen reader is active (#8357)

* [PM-2871] Submenu UI elements cannot be navigated through keyboard when screen reader is active

* [PM-2871] Adding an aria-hidden value to menu divider elements

libs/components/src/menu/menu-divider.component.html

@@ -1,4 +1,5 @@
 <div
   class="tw-my-2 tw-border-0 tw-border-t tw-border-solid tw-border-t-secondary-500"
   role="separator"
+  aria-hidden="true"
 ></div>

libs/components/src/menu/menu-trigger-for.directive.ts

@@ -88,6 +88,7 @@ export class MenuTriggerForDirective implements OnDestroy {
       }
       this.destroyMenu();
     });
+    this.menu.keyManager.setFirstItemActive();
     this.keyDownEventsSub =
       this.menu.keyManager &&
       this.overlayRef