Use md5 implementation of RustCrypto organization

[petrosagg]

Motivation and Context

I noticed that the S3 SDK was depending to the md5 crate which is not part of the RustCrypto organization. The RustCrypto organization is the de-facto standard of cryptographic primitive implementations in Rust with an active community and already used by aws-smithy-checksums for its sha1 and sha2 checksums.

Description

I changed the md5 crate to the one provided by RustCrypto.

Testing

No behavior changes to be tested

Checklist

• I have updated CHANGELOG.next.toml if I made changes to the AWS SDK, generated SDK code, or SDK runtime crates

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[jdisanti]

Thank you for the contribution! These changes look good to me, but I will need to dig into why it's failing in CI. It's kind of a strange failure since the md5 symbol is being used generate the code, and that should pull in the md-5 dependency automatically.

[jdisanti]

It looks like the md-5 crate renames itself to md5:
https://github.com/RustCrypto/hashes/blob/master/md5/Cargo.toml#L14-L15

Our codegen doesn't currently support that concept, so I think this will require adding a property to CargoDependency and updating either the CargoTomlGenerator to re-rename the crate, or the RustWriter to use the different name.

[petrosagg]

@jdisanti I see, I pushed a change that should fix that, let's see what CI thinks about it

[Velfi]

@petrosagg It looks like the codegen tests are still failing with a naming issue. You can run codegen locally to check for this with ./gradlew :aws:sdk:cargoCheck. Let me know if that doesn't work for you.

[jdisanti]

It looks like that this.name.replace("-", "_") snippet was in two places. Easy fix. Thanks for contributing this!

[petrosagg]

@jdisanti oh, great! Thanks for looking into it, it would have been a deep rabbit hole to set up a local devenv for me, I've never worked with Java nor Kotlin before :)