Remove redundant aria label for JS toast messages

[cconard96]

Checklist before requesting a review

• I have read the CONTRIBUTING document.
• I have performed a self-review of my code.

Description

Noticed with Forms that HTML content wasn't handled properly for JS toast messages when using it in an aria-label attribute. It wasn't escaped, but also the label is completely redundant and would be annoying for screen reader users. Change was added in #19355.

The way it was, as soon as the message appeared the screen reader would announce:

1. The message content
2. The message title
3. The close button
4. The message content

Screenshots (if appropriate):

[AdrienClairembault]

I think some E2E tests might need it, but ok for me if tests are green

[cconard96]

Is there a reason the tests aren't just looking for an alert role element that contains the expected message rather than an alert with the entire message as its name?

[AdrienClairembault]

I think the original issue that lead to this change is that there are two alerts on the page (if I remember correctly).

[AdrienClairembault]

Should be good with your change tho, waiting for the CI to confirm.

[github-actions]

This PR has been is closed and has been automatically locked. Please open a new issue with all requested information for related bugs.