test(many): replace waitForSelector with waitFor (#28888)

Issue number: N/A

---------

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## What is the current behavior?
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There are some tests that use Playwright's `waitForSelector`
[function](https://playwright.dev/docs/api/class-page#page-wait-for-selector).
However, Playwright has informed the community to not use this function
by labeling it as
[discouraged](https://playwright.dev/docs/api/class-page#page-wait-for-selector).

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

- Replaced `waitForSelector` with the
[recommended](https://playwright.dev/docs/api/class-page#page-wait-for-selector)
`waitFor`
[function](https://playwright.dev/docs/api/class-locator#locator-wait-for).

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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## Other information

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

N/A

core/src/components/button/test/basic/button.e2e.ts

@@ -57,7 +57,7 @@ configs({ modes: ['md'] }).forEach(({ config, screenshot, title }) => {
         await page.mouse.down();
       }
 
-      await page.waitForSelector('#default.ion-activated');
+      await page.locator('#default.ion-activated').waitFor();
 
       await expect(button).toHaveScreenshot(screenshot(`button-ripple-effect`));
     });