Enable file nesting for unit test files in vscode (#45329)

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Adds support for this type of nesting of files in the VSCode explorer.

![CleanShot 2023-01-27 at
[email protected]](https://graphite-user-uploaded-assets-prod.s3.amazonaws.com/VceFdFT9YKEsQBBXXDFJ/74cd9a65-094a-491e-aadd-d65ba63c5b9d/CleanShot%202023-01-27%20at%[email protected])

## Bug

- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)

## Feature

- [ ] Implements an existing feature request or RFC. Make sure the
feature request has been accepted for implementation before opening a
PR.
- [ ] Related issues linked using `fixes #number`
- [ ]
[e2e](https://github.com/vercel/next.js/blob/canary/contributing/core/testing.md#writing-tests-for-nextjs)
tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)

## Documentation / Examples

- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)

.vscode/settings.json

@@ -50,5 +50,12 @@
   ],
 
   // Disable TypeScript surveys.
-  "typescript.surveys.enabled": false
+  "typescript.surveys.enabled": false,
+
+  // Enable file nesting for unit test files.
+  "explorer.fileNesting.enabled": true,
+  "explorer.fileNesting.patterns": {
+    "*.ts": "$(capture).test.ts, $(capture).test.tsx",
+    "*.tsx": "$(capture).test.ts, $(capture).test.tsx"
+  }
 }