fix(cli): delete temp file after extraction (#40259)

Follow-up on the review comment #40182 (comment) since the PR was merged.

## Bug

- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have helpful link attached, see `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`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have helpful link attached, see `contributing.md`

## Documentation / Examples

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

packages/create-next-app/helpers/examples.ts

@@ -5,7 +5,7 @@ import { Stream } from 'stream'
 import { promisify } from 'util'
 import { join } from 'path'
 import { tmpdir } from 'os'
-import { createWriteStream } from 'fs'
+import { createWriteStream, promises as fs } from 'fs'
 
 const pipeline = promisify(Stream.pipeline)
 
@@ -83,7 +83,7 @@ export function existsInRepo(nameOrUrl: string): Promise<boolean> {
 }
 
 async function downloadTar(url: string) {
-  const tempFile = join(tmpdir(), `next.js-cra-example.temp-${Date.now()}`)
+  const tempFile = join(tmpdir(), `next.js-cna-example.temp-${Date.now()}`)
   await pipeline(got.stream(url), createWriteStream(tempFile))
   return tempFile
 }
@@ -105,6 +105,8 @@ export async function downloadAndExtractRepo(
         `${name}-${branch.replace(/\//g, '-')}${filePath ? `/${filePath}` : ''}`
       ),
   })
+
+  await fs.unlink(tempFile)
 }
 
 export async function downloadAndExtractExample(root: string, name: string) {
@@ -122,4 +124,6 @@ export async function downloadAndExtractExample(root: string, name: string) {
     strip: 3,
     filter: (p) => p.includes(`next.js-canary/examples/${name}`),
   })
+
+  await fs.unlink(tempFile)
 }