chore: bump the vitest group across 1 directory with 2 updates

Bumps the vitest group with 2 updates in the / directory: [@cloudflare/vitest-pool-workers](https://github.com/cloudflare/workers-sdk/tree/HEAD/packages/vitest-pool-workers) and [vitest](https://github.com/vitest-dev/vitest/tree/HEAD/packages/vitest).


Updates `@cloudflare/vitest-pool-workers` from 0.10.1 to 0.15.1
- [Release notes](https://github.com/cloudflare/workers-sdk/releases)
- [Changelog](https://github.com/cloudflare/workers-sdk/blob/main/packages/vitest-pool-workers/CHANGELOG.md)
- [Commits](https://github.com/cloudflare/workers-sdk/commits/@cloudflare/vitest-pool-workers@0.15.1/packages/vitest-pool-workers)

Updates `vitest` from 3.2.4 to 4.1.5
- [Release notes](https://github.com/vitest-dev/vitest/releases)
- [Commits](https://github.com/vitest-dev/vitest/commits/v4.1.5/packages/vitest)

---
updated-dependencies:
- dependency-name: "@cloudflare/vitest-pool-workers"
  dependency-version: 0.12.1
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: vitest
- dependency-name: vitest
  dependency-version: 4.0.16
  dependency-type: direct:development
  update-type: version-update:semver-major
  dependency-group: vitest
...

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Author: dependabot[bot]