Create Alert Dialog component

[Rajdeepc]

Spectrum CSS PR

adobe/spectrum-css#1862

Acceptance Criteria

• Create an RFC that discusses what needs to be built, what affects it'll have, how folks will migrate, etc
• Review RFC with team
• Upon consensus create/convert ticket(s) needed to build the component
• Add storybook and Unit Tests

What needs to be built?

New Alert-dialog component in SWC.
https://pr-1862--spectrum-css.netlify.app/alertdialog

What effects it'll have?

New Alert Dialog Component

How to migrate?

1. Adding the new package in tsconfig-all.json
2. Updating alert-dialog/tsconfig.json to import shared and base config
3. Adding button and icon dependencies
4. To make sure we have something like :host[variant='confirmation'] etc. we need to add a property in spectrum-config.ts to update the spectrum generated css file to create css classnames like above.