feat: add auto increment transformer

[p5quared]

Draft Conditions

This PR is a draft because there are a few things I am aware of and have to modify/finish before it is worthy of formal review:

• API Name Review: I know that the PR says @generated and the implementation is @sequence. After reaching a consensus I will modify the names as necessary.
  • Update Names: Settled on @default
• E2E Changes: The E2E tests as they are setup are mostly an exercise and I ran them by disabling validations on the transformer. Mainly I need to rewrite using a mock Postgres datasource.
• Docs: I wrote documentation in this repo in a place or two but will follow up on places that I may be missing/update docs website as necessary.

Description of changes

Implements a transformer for @generated along with appropriate unit and e2e tests.

CDK / CloudFormation Parameters Changed

N/a

Issue #, if available

#815
(#815 (comment))

Description of how you validated changes

Unit and E2E tests. Also tested with sample app.

Checklist

• PR description included
• yarn test passes
• Tests are changed or added
• Relevant documentation is changed or added (and PR referenced)

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[p5quared]

Functionally, this transformer implementation is nearly identical to the default transformer. It differs in the following ways:

• no resolver changes
• different set of field validations
• It also mutates the GraphQL schema inputs while the default transformer does not (fix: un-require required input fields with @default #2867).

[p5quared]

Closing as I am going to replace this with a formal PR with the approved API.