fix: ensure File is pollyfilled for Node 18.11+

[eltigerchino]

fixes #10946

Quick fix that ensures File is always polyfilled rather than just pre Node 18.11.0. The global was only added in Node 20, while buffer.File was only added in Node 18.13.0
https://nodejs.org/dist/latest-v20.x/docs/api/globals.html#class-file

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[dummdidumm]

Mhhhhhm does this interfer with undici now again, as in "different versions are used and undici breaks", because File could come from our undici version and the other stuff could come from the built-in undici version?

[gtm-nayan]

Could but looks like File at least has some leeway by virtue of being based on Blob so undici has some quacks-like-a-duck logic to prevent such errors. Also on 18.13+ both undici and our polyfill try to use the File from buffer first so newer versions should not have any mismatches