fix: ensure esc key does not close modals that are blocking

[adamstankiewicz]

Description

The Paragon modal components (e.g., AlertModal) generally rely on the underlying ModalDialog component and it's optional props such as isBlocking. The intent for isBlocking should prevent the modal from being dismissed for use cases where there is a required action to be taken within the modal. However, isBlocking only prevents clicking of the modal backdrop from dismissing modal; users may still press the Escape key to dismiss the modal, despite the intent to have the modal be blocking.

This PR ensures the Escape behavior when isBlocking is passed to modal components such as AlertModal follows the same behavior as the modal backdrop; that is, when a modal isBlocking, neither clicking the modal backdrop or pressing Escape key should dismiss the modal.

Deploy Preview

https://deploy-preview-3033--paragon-openedx.netlify.app/components/modal/alert-modal/

How to test:

• On the "Basic usage" on the linked deploy preview, add the isBlocking prop to the AlertModal component.
• Observe that neither clicking on the modal backdrop or pressing Escape key dismisses the blocking modal.

Merge Checklist

• If your update includes visual changes, have they been reviewed by a designer? Send them a link to the Netlify deploy preview, if applicable.
• Does your change adhere to the documented style conventions?
• Do any prop types have missing descriptions in the Props API tables in the documentation site (check deploy preview)?
• Were your changes tested using all available themes (see theme switcher in the header of the deploy preview, under the "Settings" icon)?
• Were your changes tested in the example app?
• Is there adequate test coverage for your changes?
• Consider whether this change needs to reviewed/QA'ed for accessibility (a11y). If so, please add wittjeff and adamstankiewicz as reviewers on this PR.

Post-merge Checklist

• Verify your changes were released to NPM at the expected version.
• If you'd like, share your contribution in #show-and-tell.
• 🎉 🙌 Celebrate! Thanks for your contribution.

[netlify]

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[openedx-semantic-release-bot]

🎉 This PR is included in version 22.2.2 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀