Bump webpack-dev-server from 1.16.5 to 5.2.6 in /samples/graphiql-client

Bumps [webpack-dev-server](https://github.com/webpack/webpack-dev-server) from 1.16.5 to 5.2.6.
- [Release notes](https://github.com/webpack/webpack-dev-server/releases)
- [Changelog](https://github.com/webpack/webpack-dev-server/blob/v5.2.6/CHANGELOG.md)
- [Commits](webpack/webpack-dev-server@v1.16.5...v5.2.6)

---
updated-dependencies:
- dependency-name: webpack-dev-server
  dependency-version: 5.2.6
  dependency-type: direct:development
...

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Author: dependabot[bot]