[omnibox] Bump flag expiry for pedals related flags

Bug: 893183
Change-Id: I748442cacfd78d8c5a92bc2cbba0eff05f6bf8b5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3373216


Reviewed-by: Tibor Goldschwendt <tiborg@chromium.org>
Commit-Queue: Orin Jaworski <orinj@chromium.org>
Cr-Commit-Position: refs/heads/main@{#956776}