Tech debt: Audit unit tests and replace external dependencies by mocks

[phipag]

Why is this needed?

Currently, some unit tests such as powertools-idempotency-dynamodb depend on running a local server for mocking AWS resources.

This violates the principle that unit tests should run in a self-contained way.

Example which should be avoided:

https://github.com/aws-powertools/powertools-lambda-java/blob/7b18029dff8f86cb9be6be8cbc4567aaacbec418/powertools-idempotency/powertools-idempotency-dynamodb/src/test/java/software/amazon/lambda/powertools/idempotency/persistence/dynamodb/DynamoDBConfig.java#L50-L55

This starts a DynamoDB mock server on localhost.

Which area does this relate to?

Tests

Suggestion

This issues suggests to:

1. Audit all unit tests for external dependencies
2. Replace external dependencies by self-contained mocking
3. Add a test scenario in the end2end tests to cover the use-case using real infrastructure in real AWS accounts

Acknowledgment

• [x] This request meets Powertools for AWS Lambda (Python) Tenets
• [ ] Should this be considered in other Powertools for AWS Lambda languages? i.e. Python, TypeScript, and .NET