Support migration from AWS CodeCommit (#31981)
This PR adds support for migrating repos from [AWS
CodeCommit](https://docs.aws.amazon.com/codecommit/latest/userguide/welcome.html).
The access key ID and secret access key are required to get repository
information and pull requests. And [HTTPS Git
credentials](https://docs.aws.amazon.com/codecommit/latest/userguide/setting-up-gc.html)
are required to clone the repository.
<img
src="https://github.com/user-attachments/assets/82ecb2d0-8d43-42b0-b5af-f5347a13b9d0"
width="680" />
The AWS CodeCommit icon is from [AWS Architecture
Icons](https://aws.amazon.com/architecture/icons/).
<img
src="https://github.com/user-attachments/assets/3c44d21f-d753-40f5-9eae-5d3589e0d50d"
width="320" />
