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

Issue number: Internal

---------

<!-- Please do not submit updates to dependencies unless it fixes an
issue. -->

<!-- Please try to limit your pull request to one type (bugfix, feature,
etc). Submit multiple pull requests if needed. -->

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

Several tests were still using the legacy form syntax.

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

<!--
  If this introduces a breaking change:
1. Describe the impact and migration path for existing applications
below.
  2. Update the BREAKING.md file with the breaking change.
3. Add "BREAKING CHANGE: [...]" to the commit description when merging.
See
https://github.com/ionic-team/ionic-framework/blob/main/.github/CONTRIBUTING.md#footer
for more information.
-->


## Other information

<!-- Any other information that is important to this PR such as
screenshots of how the component looks before and after the change. -->

---------

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

core/src/components/modal/test/sheet/index.html

@@ -85,10 +85,7 @@
         </ion-header>
 
         <ion-content class="ion-padding">
-          <ion-item>
-            <ion-label>Input outside modal</ion-label>
-            <ion-input id="root-input" legacy="true"></ion-input>
-          </ion-item>
+          <input id="root-input" />
 
           <ion-button id="sheet-modal" onclick="presentModal()">Present Sheet Modal</ion-button>
           <ion-button

core/src/components/modal/test/sheet/modal.e2e.ts

@@ -52,7 +52,7 @@ configs({ modes: ['ios'], directions: ['ltr'] }).forEach(({ title, config }) =>
 
       await ionModalDidPresent.next();
 
-      const input = page.locator('#root-input input').first();
+      const input = page.locator('#root-input').first();
       await input.click();
       await expect(input).toBeFocused();
     });

core/src/components/modal/test/spec/index.html

@@ -60,8 +60,7 @@
 
         <ion-content>
           <ion-item>
-            <ion-label>Use Custom Animation</ion-label>
-            <ion-toggle></ion-toggle>
+            <ion-toggle>Use Custom Animation</ion-toggle>
           </ion-item>
 
           <ion-list id="list"></ion-list>