Bump aws-sigv4 from 0.54.1 to 0.54.2

Bumps [aws-sigv4](https://github.com/awslabs/smithy-rs) from 0.54.1 to 0.54.2.
- [Release notes](https://github.com/awslabs/smithy-rs/releases)
- [Changelog](https://github.com/awslabs/smithy-rs/blob/main/CHANGELOG.md)
- [Commits](https://github.com/awslabs/smithy-rs/commits)

---
updated-dependencies:
- dependency-name: aws-sigv4
  dependency-type: indirect
...

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Author: dependabot[bot]