[Feature]: Provide debug mode

### Self-service

- [ ] I'd be willing to implement this feature

### Problem

The only debugging which aws-sdk-js-codemod uses is the one provided by JSCodeShift.

There's no additional debug option available, which can provide information on what transformation was done.

### Solution

Add a CLI option (say `--debug`) to add debug mode.

### Alternatives

N/A

### Additional context

Tip from CLI best practices: https://github.com/lirantal/nodejs-cli-apps-best-practices#63-provide-debug-mode

Start at the CLI entry point and trace how the tool invokes JSCodeShift and reports transformations. Define the debug output from the issue's requirement, then verify that invoking the new option reports what transformation was performed while normal runs remain unchanged.

Written by the indexing model from the issue text.