feat(ErrorPrevention): Add modal usage guidelines

What does this MR do?

This MR adds guidelines for using modals for confirming destructive actions in the product. It's aimed to help resolve the inconsistency in how destructive action confirmation modals are used today. For more content see this Slack thread (internal).

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  • For example, if the MR is focused on usage guidelines, addressing accessibility challenges could be added in a separate MR.
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