Bump aws/aws-sdk-php in /php/example_code/class_examples

Bumps [aws/aws-sdk-php](https://github.com/aws/aws-sdk-php) from 3.293.9 to 3.371.4.
- [Release notes](https://github.com/aws/aws-sdk-php/releases)
- [Commits](aws/aws-sdk-php@3.293.9...3.371.4)

---
updated-dependencies:
- dependency-name: aws/aws-sdk-php
  dependency-version: 3.371.4
  dependency-type: direct:production
...

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Author: dependabot[bot]