chore(deps-dev): bump serve-static in /references/java-callout/proxy-v1

Bumps [serve-static](https://github.com/expressjs/serve-static) from 1.13.2 to 1.16.0.
- [Release notes](https://github.com/expressjs/serve-static/releases)
- [Changelog](https://github.com/expressjs/serve-static/blob/master/HISTORY.md)
- [Commits](expressjs/serve-static@v1.13.2...1.16.0)

---
updated-dependencies:
- dependency-name: serve-static
  dependency-type: indirect
...

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