feat: Add a.authorizationBuilder and AuthorizationCallback to support reusable authorization

[stocaaro]

Description of changes:
Developers want to reuse authentication definition. Different parts of the schema can be authenticated in different ways, which makes the types complicated.

This change introduces a.authorizationBuilder example usage:

const sharedAuth = a.authorizationBuilder((allow) => [a.guest()])

The tests explore different authorization feature combinations. Customers can override the defaults by identifying their usage in a generic. Example:

const sharedAuth = a.authorizationBuilder<'schema'>((allow) => [a.resource(exampleFcn)])

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[changeset-bot]

🦋 Changeset detected

Latest commit: 88f30b5

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

This PR includes changesets to release 1 package

Name	Type
@aws-amplify/data-schema	Minor

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