feat(toggle): add required prop (#30156)

Issue number: resolves internal

---------

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## What is the current behavior?
- Currently, the screen reader do not announce the component as required
when `required={true}`.

## What is the new behavior?
- Added a new `required` prop to be used for accessibility purposes that
adds the `required` attribute to toggle's inner native input.

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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

@@ -75,3 +75,33 @@ describe('ion-toggle: disabled', () => {
     expect(toggle.checked).toBe(false);
   });
 });
+
+describe('ion-toggle: required', () => {
+  it('should have a required attribute in inner input when true', async () => {
+    const page = await newSpecPage({
+      components: [Toggle],
+      html: `
+        <ion-toggle required="true">Toggle</ion-toggle>
+      `,
+    });
+
+    const toggle = page.body.querySelector('ion-toggle')!;
+    const nativeInput = toggle.shadowRoot?.querySelector('input[role=switch]')!;
+
+    expect(nativeInput.hasAttribute('required')).toBeTruthy();
+  });
+
+  it('should not have a required attribute in inner input when false', async () => {
+    const page = await newSpecPage({
+      components: [Toggle],
+      html: `
+        <ion-toggle required="false">Toggle</ion-toggle>
+      `,
+    });
+
+    const toggle = page.body.querySelector('ion-toggle')!;
+    const nativeInput = toggle.shadowRoot?.querySelector('input[role=switch]')!;
+
+    expect(nativeInput.hasAttribute('required')).toBeFalsy();
+  });
+});

core/src/components/toggle/toggle.tsx

@@ -108,6 +108,13 @@ export class Toggle implements ComponentInterface {
    */
   @Prop() alignment?: 'start' | 'center';
 
+  /**
+   * If true, screen readers will announce it as a required field. This property
+   * works only for accessibility purposes, it will not prevent the form from
+   * submitting if the value is invalid.
+   */
+  @Prop() required = false;
+
   /**
    * Emitted when the user switches the toggle on or off.
    *
@@ -290,7 +297,8 @@ export class Toggle implements ComponentInterface {
   }
 
   render() {
-    const { activated, color, checked, disabled, el, justify, labelPlacement, inputId, name, alignment } = this;
+    const { activated, color, checked, disabled, el, justify, labelPlacement, inputId, name, alignment, required } =
+      this;
 
     const mode = getIonMode(this);
     const value = this.getValue();
@@ -327,6 +335,7 @@ export class Toggle implements ComponentInterface {
             onFocus={() => this.onFocus()}
             onBlur={() => this.onBlur()}
             ref={(focusEl) => (this.focusEl = focusEl)}
+            required={required}
             {...this.inheritedAttributes}
           />
           <div