[samples] Add cbruni as owner

Change-Id: I5b5024fdcf4806b6e91112448db3c334f9ede48b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2821957
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Mathias Bynens <mathias@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73938}

samples/OWNERS

 mathias@chromium.org
-yangguo@chromium.org
+cbruni@chromium.org