ngbAccordionCollapse does not collapse when ngbAccordionItem is disabled

Bug description:

When an ngbAccordionItem is disabled, the ngbAccordionCollapse is not collapsed (and the content is not disabled). This is a breaking change from the component-based accordion.

Compare the "Custom header" demo in the current version with the old release (https://ng-bootstrap.github.io/releases/13.x/#/components/accordion/examples).

Link to minimally-working StackBlitz that reproduces the issue:

Based on the default "Custom header" demo: https://stackblitz.com/edit/angular-oz5acv?file=src%2Fapp%2Faccordion-header.html,src%2Fapp%2Faccordion-header.ts:

• Open the third panel
• The button can be clicked
• Click on the "Disable third" button on the second panel
• The third panel's header is disabled, but the panel remains open, and the button can be clicked!

Versions of Angular, ng-bootstrap and Bootstrap:

Angular: 17.0.9

ng-bootstrap: 16.0.0

Bootstrap: 5.3.2

Reproduce the issue using the StackBlitz files src/app/accordion-header.html and src/app/accordion-header.ts: open the third panel, then disable it from the second panel. Trace the accordion item and collapse behavior in the ng-bootstrap source, and verify that disabling an open item collapses its panel and prevents interaction with its content.