Bump minor for some runtime crates as part of S3 Express (#3477)

## Description
- Bump minor for `aws-sigv4` for [these
changes](https://github.com/smithy-lang/smithy-rs/pull/3465/files#diff-154d03aaceb2d08722c365acf156e47c523638765a8a645c350cff72550c80dd)
- Bump minor for `aws-smithy-runtime-api` for [these
changes](https://github.com/smithy-lang/smithy-rs/pull/3465/files#diff-daa7b9cc6f272b9b914593b1ce032b87af4fe17c351fee5608d621bdac091040)

## Testing
Existing tests in CI

## Checklist
<!--- If a checkbox below is not applicable, then please DELETE it
rather than leaving it unchecked -->
- [x] I have updated `CHANGELOG.next.toml` if I made changes to the
smithy-rs codegen or runtime crates
- [x] I have updated `CHANGELOG.next.toml` if I made changes to the AWS
SDK, generated SDK code, or SDK runtime crates

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