chore(deps)(deps): bump the nestjs group in /backend with 4 updates

Bumps the nestjs group in /backend with 4 updates: [@nestjs/common](https://github.com/nestjs/nest/tree/HEAD/packages/common), [@nestjs/core](https://github.com/nestjs/nest/tree/HEAD/packages/core), [@nestjs/platform-express](https://github.com/nestjs/nest/tree/HEAD/packages/platform-express) and [@nestjs/testing](https://github.com/nestjs/nest/tree/HEAD/packages/testing).


Updates `@nestjs/common` from 11.1.6 to 11.1.8
- [Release notes](https://github.com/nestjs/nest/releases)
- [Commits](https://github.com/nestjs/nest/commits/v11.1.8/packages/common)

Updates `@nestjs/core` from 11.1.6 to 11.1.8
- [Release notes](https://github.com/nestjs/nest/releases)
- [Commits](https://github.com/nestjs/nest/commits/v11.1.8/packages/core)

Updates `@nestjs/platform-express` from 11.1.6 to 11.1.8
- [Release notes](https://github.com/nestjs/nest/releases)
- [Commits](https://github.com/nestjs/nest/commits/v11.1.8/packages/platform-express)

Updates `@nestjs/testing` from 11.1.6 to 11.1.8
- [Release notes](https://github.com/nestjs/nest/releases)
- [Commits](https://github.com/nestjs/nest/commits/v11.1.8/packages/testing)

---
updated-dependencies:
- dependency-name: "@nestjs/common"
  dependency-version: 11.1.8
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: nestjs
- dependency-name: "@nestjs/core"
  dependency-version: 11.1.8
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: nestjs
- dependency-name: "@nestjs/platform-express"
  dependency-version: 11.1.8
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: nestjs
- dependency-name: "@nestjs/testing"
  dependency-version: 11.1.8
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: nestjs
...

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Author: dependabot[bot]