[DTO-5004][BpkInfoBanner] Remove Alert Role

[Iain530]

Currently when an info banner is render on a page, the screenreader will immediately switch to reading out the title text. This happens because we treat the info banner as an alert for screen readers. The documentation says the alert role shouldn’t be used for elements rendered on page load. Since this component is used more as a styling container than an alert dialog it should only be read in the normal page flow.

Bug caused by alert role (sound on)

RPReplay_Final1701948086.2.MP4

Remember to include the following changes:

• Ensure the PR title includes the name of the component you are changing so it's clear in the release notes for consumers of the changes in the version e.g [KOA-123][BpkButton] Updating the colour
• README.md (If you have created a new component)
• Component README.md
• Tests
• Storybook examples created/updated
• For breaking changes or deprecating components/properties, migration guides added to the description of the PR. If the guide has large changes, consider creating a new Markdown page inside the component's docs folder and link it here

[Iain530]

presentation seemed like the most sensible value to me here as it removes it as a landmark which this probably. These banners are probably to be used as part of a section of the page and not contain a whole section themselves? https://developer.mozilla.org/en-US/docs/Web/HTML/Element/section

[github-actions]

	Warnings
⚠️	Package source files (e.g. packages/package-name/src/Component.tsx) were updated, but type files weren't. Have you checked that no types have changed?

Browser support

If this is a visual change, make sure you've tested it in multiple browsers.

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[github-actions]

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[github-actions]

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