Add aliases support to build_script.template

[scasagrande]

This PR adds support for generated BUILD files containing cargo_build_script to make use of the aliases keyword.

The need for this was discovered when using cargo raze on a project that pulled in value-bag as a sub-dependency. This project requires an alias of version-check as rustc in order to run build.rs.

Copy-pasting the code block from common-attrs where this has already been solved for rust_library adds the same solution to cargo_build_script.

I am a Rust noob, so if this isn't the best-practices solution to this problem, feel free to close.

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[dfreese]

looks good to me. Can you merge in the latest main to pick up some clippy fixes? If it still passes CI after that, I'm good with this.

[scasagrande]

Thanks @dfreese ! I have updated my branch, and it looks like we just need CI to be approved to run again

[dfreese]

Still have this on my plate. #477 made me want to double check first that this wouldn't cause breakages by unintentionally adding aliases on build dependencies. I don't know off hand if they should be shared between build and normal deps.

[scasagrande]

No problem @dfreese . I'm jumping between many different problems in my bazel adventure, so as I learn more I might be able to cycle back and more rigorously implement this change