test: migrate form control usages to modern syntax (#28897)

Issue number: Internal

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## What is the current behavior?
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Several tests were still using the legacy form syntax.

## What is the new behavior?
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this PR. -->

- Migrated tests in `core`, `angular`, and `vue` to use the modern form
syntax (`react` did not have form controls).

I opted not to migrate `item/test/highlight` and `item/test/counter`
because those tests are going to be removed in the future once the
deprecate item APIs are removed.

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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  2. Update the BREAKING.md file with the breaking change.
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## Other information

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

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Co-authored-by: ionitron <hi@ionicframework.com>
Co-authored-by: Maria Hutt <thetaPC@users.noreply.github.com>

core/src/components/popover/test/basic/index.html

@@ -212,7 +212,7 @@
           connectedCallback() {
             this.innerHTML = `
           <ion-content>
-            <ion-textarea rows="4" style="max-height: 44px; overflow-y: auto;" value="the cursor in this <ion-textarea>\nmust be able to be moved\nwith the arrow keys and\nhome and end keys"></ion-textarea>
+            <ion-textarea aria-label="textarea" rows="4" style="max-height: 44px; overflow-y: auto;" value="the cursor in this <ion-textarea>\nmust be able to be moved\nwith the arrow keys and\nhome and end keys"></ion-textarea>
             <textarea rows="4" style="display:block;width: 100%;border: 0;padding: 8px; max-height: 44px; overflow-y: auto">the cursor in this <textarea>\nmust be able to be moved\nwith the arrow keys and\nhome and end keys</textarea>
           </ion-content>
         `;