feat: add onClose feature to CommonMessage

[jaredcwhite]

Issue Overview

This PR addresses #80

Description

You can now pass an onClose prop with a callback to any of the CommonMessage components (Alert, Message, and Toast—but this is primarily for use with Alert).

How Can This Be Tested/Reviewed?

There's an example in Storybook here: https://deploy-preview-81--storybook-ui-seeds.netlify.app/?path=/story/blocks-alert--wide-container-layout

Checklist:

• [ ] I have added QA notes to the issue with applicable URLs
• [x] I have performed a self-review of my own code
• [x] I have reviewed the changes in a desktop view
• [ ] I have reviewed the changes in a mobile view
• [ ] I have made corresponding changes to the documentation
• [x] My changes generate no new warnings
• [x] I have added tests that prove my fix is effective or that my feature works
• [ ] I have exported any new components
• [x] My commit message(s) and PR title are polished in the conventional commit format, and any breaking changes are indicated in the message and are well-described

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[github-actions[bot]]

:tada: This PR is included in version 1.13.0 :tada:

The release is available on:

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

Your semantic-release bot :package::rocket: