[google_apis/gaia] Remove blundell as OWNER

My addition as OWNER was to ease a refactoring that has since been
completed. I am not a suitable general-purpose OWNER.

Change-Id: Ib6a3acb5231641644676cac4daa531cde4e9f407
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3861971


Auto-Submit: Colin Blundell <blundell@chromium.org>
Reviewed-by: Mihai Sardarescu <msarda@chromium.org>
Commit-Queue: Mihai Sardarescu <msarda@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1040965}