Context

The AWS SDK V2 is being deprecated. We need to remove all uses of it from the CDK.

Task Description

This is likely to be the most complex change for removing sdkv2.

We have custom logic to allow users to either use sdk v2 or sdk v3. It also uses the sdk-v2-to-v3 adapter extensively. All custom resources will need to be tested, not just for hash changes, but for deployability. Some manual validation may be required.

This package is also copied into aws-cdk-lib at build time to avoid circular dependencies. If sdk-v2-to-v3-adapter is no longer used, it appears that both will no longer be needed and that the remaining functionality needed from this package could exist solely in aws-cdk-lib/custom-resources.

This package also uses aws-sdk-mock to generate mocks. Either a suitable replacement will need to be found for v3, or new mocks will need to be written. One further consideration is that the upgrade effectively disallows users from using node16 runtimes. The deprecation date for node16 Lambda runtimes is June 12, 2024. Lambda will block function creation on July 16, 2024 and will block function updates on August 15, 2024.

Acceptance Criteria

1. Document that we are leaving the sdk-v2-to-v3-adapter in place.
2. Update SDKv3-09 to include the plan decided on in the acceptance criteria.
3. Remove all other uses of SDKv2.
4. Update relevant integ tests and verify that the impacted custom resources successfully deploy and behave as expected.