bug: header value checks are too strict in fetch

Bug Description

https://github.com/nodejs/undici/blob/0964a83710467b994cc108d096e97f69dd54ac90/lib/core/request.js#L26

The regex here is too strict for fetch which causes a bunch of tests to fail:

{ fail: '\x01' }
{ fail: '\x02' }
{ fail: '\x03' }
{ fail: '\x04' }
{ fail: '\x05' }
{ fail: '\x06' }
{ fail: '\x07' }
{ fail: '\b' }
{ fail: '\x0E' }
{ fail: '\x0F' }
{ fail: '\x10' }
{ fail: '\x11' }
{ fail: '\x12' }
{ fail: '\x13' }
{ fail: '\x14' }
{ fail: '\x15' }
{ fail: '\x16' }
{ fail: '\x17' }
{ fail: '\x18' }
{ fail: '\x19' }
{ fail: '\x1A' }
{ fail: '\x1B' }
{ fail: '\x1C' }
{ fail: '\x1D' }
{ fail: '\x1E' }
{ fail: '\x1F' }

Reproducible By

https://gist.github.com/KhafraDev/cc178abba0a89580008f44c7ebee76a3

Sorry for the messy code it was taken almost directly from wpt (https://github.com/web-platform-tests/wpt/blob/master/fetch/api/headers/header-values-normalize.any.js)

Expected Behavior

The tests should pass.

Logs & Screenshots

Environment

Additional context

These checks were added in a29a151d to fix an issue where headers weren't being sanitized.

cc @mcollina

According to the spec, a header value is a string (or Uint8Array, etc) that has no leading or trailing whitespace and doesn't contain \0 or LF or CR.

Also see https://github.com/httpwg/http-core/issues/19#issuecomment-271903665

and the spec

The definition of header value is not defined in terms of an HTTP token production as it is broken

Read lib/core/request.js at line 26 and compare its header-value check with the linked Fetch and WPT expectations. Reproduce the listed failing cases from the gist or relevant WPT test, then verify that the affected tests pass while NUL, LF, and CR remain rejected.