fix(gatsby): fetching 404 page with path prefix

[iChenLei]

Description

Add e2e test for PR #32528

Closes #32142 and #31504.
Adds the pathPrefix on the doFetch action that checks for 404 page existence. This previously was called without prefix, causing React to break when the resource existed on the root path or a 302 redirect were returned.

Current behaviour

404 page with pathPrefix, broken React rendering (react hydrate), just a static markup( just like only call ReactDOMServer.renderToString(<Page-404 />) )

Expected behaviour

React hydrate success, you can interactive with your gatsby 404 page

Don't care the console error output, it's just a debug test.

console.error("`${__PATH_PREFIX__}${rawPath}`", `${__PATH_PREFIX__}${rawPath}`);

Related Issues

#31504
#31531
#32142

[iChenLei]

https://dashboard.cypress.io/projects/pzj19c/runs/15628/test-results/67d8f849-6a84-422b-9479-84ba263f9685/video

I don't know why e2e test passed when I didn't add ${__PATH_PREFIX__}${rawPath} to loader.js, but it can reproduce on my loacl machine. cc @wardpeet