Improve Performance of code-generator

[knottnt]

Is your feature request related to a problem?
Running the ack-generate tool to build an ACK controller can take quite a long time. Often even taking several minutes to fully complete. This leads to long feedback cycles when implementing a new resource for an ACK controller.

Describe the solution you'd like
After some high level profiling of the ack-generate tool it appears that one culprit of the long run time is checking out the aws-sdk-go-v2 repo in order to retrieve the AWS model files. Using a smaller more focused repo such as api-models-aws may reduce the impact of retrieving AWS model files.

Describe alternatives you've considered
There are likely many other potential improvements that could be made to code-generation performance.

[github-actions]

Hello @knottnt 👋 Thank you for opening an issue in ACK! A maintainer will triage this issue soon.

We encourage community contributions, so if you're interested in tackling this yourself or suggesting a solution, please check out our Contribution and Code of Conduct guidelines.

You can find more information about ACK on our website.