Cert Management UI v2: create redirect from old URL to new url

Create a redirect on all supported platforms from
chrome://settings/certificates to chrome://certificate-manager if
the new UI is enabled.

chrome://settings/certificates was only on in linux and chromeos;
redirect is getting added on all platforms though for a consistent
user experience.

Change-Id: I055411b93ad4fbb655b6b95a76c47c95bbfe9c89
Bug: 40928765
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5734935
Reviewed-by: Matt Mueller <mattm@chromium.org>
Reviewed-by: John Lee <johntlee@chromium.org>
Commit-Queue: Hubert Chao <hchao@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1334912}