chore(deps): bump the cdk group in /infra-gen2 with 4 updates

Bumps the cdk group in /infra-gen2 with 4 updates: [aws-amplify](https://github.com/aws-amplify/amplify-js), [@aws-amplify/backend](https://github.com/aws-amplify/amplify-backend), [aws-cdk](https://github.com/aws/aws-cdk-cli/tree/HEAD/packages/aws-cdk) and [aws-cdk-lib](https://github.com/aws/aws-cdk/tree/HEAD/packages/aws-cdk-lib).


Updates `aws-amplify` from 6.15.8 to 6.16.2
- [Release notes](https://github.com/aws-amplify/amplify-js/releases)
- [Commits](https://github.com/aws-amplify/amplify-js/compare/aws-amplify@6.15.8...aws-amplify@6.16.2)

Updates `@aws-amplify/backend` from 1.18.0 to 1.21.0
- [Release notes](https://github.com/aws-amplify/amplify-backend/releases)
- [Commits](https://github.com/aws-amplify/amplify-backend/compare/@aws-amplify/backend@1.18.0...@aws-amplify/backend@1.21.0)

Updates `aws-cdk` from 2.1033.0 to 2.1106.0
- [Release notes](https://github.com/aws/aws-cdk-cli/releases)
- [Commits](https://github.com/aws/aws-cdk-cli/commits/aws-cdk@v2.1106.0/packages/aws-cdk)

Updates `aws-cdk-lib` from 2.225.0 to 2.238.0
- [Release notes](https://github.com/aws/aws-cdk/releases)
- [Changelog](https://github.com/aws/aws-cdk/blob/main/CHANGELOG.v2.alpha.md)
- [Commits](https://github.com/aws/aws-cdk/commits/v2.238.0/packages/aws-cdk-lib)

---
updated-dependencies:
- dependency-name: aws-amplify
  dependency-version: 6.16.2
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: cdk
- dependency-name: "@aws-amplify/backend"
  dependency-version: 1.21.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: cdk
- dependency-name: aws-cdk
  dependency-version: 2.1106.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: cdk
- dependency-name: aws-cdk-lib
  dependency-version: 2.238.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: cdk
...

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Author: dependabot[bot]