fix(accordion): inset style respects animated property (#27173)

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## What is the current behavior?
<!-- Please describe the current behavior that you are modifying. -->

- Accordion groups with `expand='inset'` ignore the `animated='false'`. 
- Accordions will render with the `accordion-animated` class regardless
of `animated='false'`.


<!-- Issues are required for both bug fixes and features. -->
Issue URL: resolves #27047 


## What is the new behavior?
<!-- Please describe the behavior or changes that are being added by
this PR. -->

- Accordion groups do not ignore `animated='false'` regardless of
`expand` value.
- Accordions render the `accordion-animated` class only when
`animated='true'`.

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

<!-- If this introduces a breaking change, please describe the impact
and migration path for existing applications below. -->


## Other information

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screenshots of how the component looks before and after the change. -->

N/A

core/src/components/accordion/accordion.tsx

@@ -417,7 +417,7 @@ export class Accordion implements ComponentInterface {
           'accordion-disabled': disabled,
           'accordion-readonly': readonly,
 
-          'accordion-animated': config.getBoolean('animated', true),
+          'accordion-animated': this.shouldAnimate(),
         }}
       >
         <div

core/src/components/accordion/test/accordion.spec.ts

@@ -163,3 +163,24 @@ it('should set default values if not provided', async () => {
 
   expect(accordion.classList.contains('accordion-collapsed')).toEqual(false);
 });
+
+// Verifies fix for https://github.com/ionic-team/ionic-framework/issues/27047
+it('should not have animated class when animated="false"', async () => {
+  const page = await newSpecPage({
+    components: [Item, Accordion, AccordionGroup],
+    html: `
+      <ion-accordion-group animated="false">
+        <ion-accordion>
+          <ion-item slot="header">Label</ion-item>
+          <div slot="content">Content</div>
+        </ion-accordion>
+      </ion-accordion-group>
+    `,
+  });
+
+  const accordionGroup = page.body.querySelector('ion-accordion-group')!;
+  const accordion = accordionGroup.querySelector('ion-accordion')!;
+
+  expect(accordionGroup.animated).toEqual(false);
+  expect(accordion.classList.contains('accordion-animated')).toEqual(false);
+});