Upgrade: [dependabot] - bump @aws-sdk/client-backup

Bumps [@aws-sdk/client-backup](https://github.com/aws/aws-sdk-js-v3/tree/HEAD/clients/client-backup) from 3.971.0 to 3.974.0.
- [Release notes](https://github.com/aws/aws-sdk-js-v3/releases)
- [Changelog](https://github.com/aws/aws-sdk-js-v3/blob/main/clients/client-backup/CHANGELOG.md)
- [Commits](https://github.com/aws/aws-sdk-js-v3/commits/v3.974.0/clients/client-backup)

---
updated-dependencies:
- dependency-name: "@aws-sdk/client-backup"
  dependency-version: 3.974.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]