Private Cargo Registry Support for Dependabot Updates

[github-product-roadmap]

Summary

With this change, Dependabot will be able to access Cargo private registries in order to provide updates to Rust dependencies that are stored in these private registries.

Intended Outcome

Customers who use private Cargo registries for their Rust dependencies cannot use Dependabot to keep those up-to-date today. With this change, they will be able to.

How will it work?

By setting up your Cargo private registry information in dependabot.yml, Dependabot will automatically reach out to and authenticate with the private registry when doing updates for your Rust dependencies.