Update enablement approach for sec-ch-width tests
There are some higher-level interop/spec issues with how to enable
sec-ch-width. This patch switches the tests to use name="Delegate-CH",
which is per-spec [1], as well as sending the Accept-CH header.
[1] https://wicg.github.io/client-hints-infrastructure/#delegate-ch-algo
Bug: 335630145
Change-Id: Id37303bce2fb73c85505262cc5543e23701bd091
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5548997
Commit-Queue: Philip Rogers pdr@chromium.org
Reviewed-by: Traian Captan tcaptan@chromium.org
Cr-Commit-Position: refs/heads/main@{#1303438}