Fix incorrect React env in particular case

[shuding]

The value of __NEXT_PRIVATE_PREBUNDLED_REACT has to be a correct React channel.

[ijjk]

Failing test suites

Commit: c3b12ac

pnpm testheadless test/e2e/middleware-fetches-with-body/index.test.ts

• Middleware fetches with body > with custom bodyParser sizeLimit (5mb) > should return 413 for body equal to 10mb

Expand output

● Middleware fetches with body › with custom bodyParser sizeLimit (5mb) › should return 413 for body equal to 10mb

expect(received).toBe(expected) // Object.is equality

Expected: 413
Received: 500

  177 |       )
  178 |
> 179 |       expect(res.status).toBe(413)
      |                          ^
  180 |
  181 |       if (!(global as any).isNextDeploy) {
  182 |         expect(res.statusText).toBe('Body exceeded 5mb limit')

  at Object.<anonymous> (e2e/middleware-fetches-with-body/index.test.ts:179:26)

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