Fix v11.0.0 types that removed the default export

[stefcameron]

Fixes #1396

My original intent was to remove the default export (a breaking change) as part of the major 11.0.0 release but I totally flopped on that by not also actually providing the named export in the code.

Now that the major release ship has sailed, this change fixes the types by reinstating the default export in the typings but marking it deprecated, while also providing the new named export alternative as the way forward.

PR Checklist

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• Issue being fixed is referenced.
• Source changes maintain:
  • Stated browser compatibility.
  • Stated React compatibility.
• Web APIs introduced have deep browser coverage, including Safari (often very late to adopt new APIs).
• Unit test coverage added/updated.
• E2E test coverage added/updated.
• Prop-types added/updated.
• Typings added/updated.
• Changes do not break SSR:
  • Careful to test typeof document/window !== 'undefined' before using it in code that gets executed on load.
• README updated (API changes, instructions, etc.).
• Changes to dependencies explained.
• Changeset added (run npm run changeset locally to add one, and follow the prompts).
  • EXCEPTION: A Changeset is not required if the change does not affect any of the source files that produce the package bundle. For example, demo changes, tooling changes, test updates, or a new dev-only dependency to run tests more efficiently should not have a Changeset since it will not affect package consumers.

[changeset-bot]

🦋 Changeset detected

Latest commit: 274d0b7

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
focus-trap-react	Patch

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[stefcameron]

This replaces #1397