Bump aws/aws-sdk-php from 3.320.7 to 3.321.2

Bumps [aws/aws-sdk-php](https://github.com/aws/aws-sdk-php) from 3.320.7 to 3.321.2.
- [Release notes](https://github.com/aws/aws-sdk-php/releases)
- [Commits](aws/aws-sdk-php@3.320.7...3.321.2)

---
updated-dependencies:
- dependency-name: aws/aws-sdk-php
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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