build(deps): bump sigs.k8s.io/gateway-api from 1.2.0 to 1.2.1 in /exa…

…mples/extension-server (#4827)

build(deps): bump sigs.k8s.io/gateway-api in /examples/extension-server

Bumps [sigs.k8s.io/gateway-api](https://github.com/kubernetes-sigs/gateway-api) from 1.2.0 to 1.2.1.
- [Release notes](https://github.com/kubernetes-sigs/gateway-api/releases)
- [Changelog](https://github.com/kubernetes-sigs/gateway-api/blob/main/RELEASE.md)
- [Commits](kubernetes-sigs/gateway-api@v1.2.0...v1.2.1)

---
updated-dependencies:
- dependency-name: sigs.k8s.io/gateway-api
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Huabing Zhao <zhaohuabing@gmail.com>