fix: ensure that mocked fetch responses have a valid URL property

[petebacondarwin]

What this PR solves / how to test

Fixes #6350

Author has addressed the following

• Tests
  • TODO (before merge)
  • Included
  • Not necessary because:
• E2E Tests CI Job required? (Use "e2e" label or ask maintainer to run separately)
  • I don't know
  • Required / Maybe required
  • Not required because:
• Changeset (Changeset guidelines)
  • TODO (before merge)
  • Included
  • Not necessary because:
• Public documentation
  • TODO (before merge)
  • Cloudflare docs PR(s):
  • Not necessary because: bug fix

[changeset-bot]

🦋 Changeset detected

Latest commit: e547406

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@cloudflare/vitest-pool-workers	Patch

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[github-actions]

A wrangler prerelease is available for testing. You can install this latest build in your project with:

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/10147086035/npm-package-wrangler-6362

You can reference the automatically updated head of this PR with:

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/prs/6362/npm-package-wrangler-6362

Or you can use npx with this latest build directly:

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/10147086035/npm-package-wrangler-6362 dev path/to/script.js

Additional artifacts:

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/10147086035/npm-package-create-cloudflare-6362 --no-auto-update

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/10147086035/npm-package-cloudflare-kv-asset-handler-6362

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/10147086035/npm-package-miniflare-6362

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/10147086035/npm-package-cloudflare-pages-shared-6362

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/10147086035/npm-package-cloudflare-vitest-pool-workers-6362

Note that these links will no longer work once the GitHub Actions artifact expires.

---

wrangler@3.67.1 includes the following runtime dependencies:

Package	Constraint	Resolved
miniflare	workspace:*	3.20240718.1
workerd	1.20240718.0	1.20240718.0
workerd --version	1.20240718.0	2024-07-18

Please ensure constraints are pinned, and miniflare/workerd minor versions match.