Bump microsoft/microsoft-graph in /app-auth/graphapponlytutorial

Bumps [microsoft/microsoft-graph](https://github.com/microsoftgraph/msgraph-sdk-php) from 3.1.0 to 3.2.0.
- [Release notes](https://github.com/microsoftgraph/msgraph-sdk-php/releases)
- [Changelog](https://github.com/microsoftgraph/msgraph-sdk-php/blob/main/CHANGELOG.md)
- [Commits](microsoftgraph/msgraph-sdk-php@v3.1.0...v3.2.0)

---
updated-dependencies:
- dependency-name: microsoft/microsoft-graph
  dependency-version: 3.2.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]