Add mattreynolds@ and chengweih@ to Web Bluetooth OWNERS files

Bug: None
Change-Id: I42d284ca21dbf65864303f66c85890e2d4c8caf8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4518989


Reviewed-by: Reilly Grant <reillyg@chromium.org>
Commit-Queue: Reilly Grant <reillyg@chromium.org>
Auto-Submit: Matt Reynolds <mattreynolds@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1146683}