Improve the reviewer coverage for traffic annotations

Bug: None
Change-Id: Iaf1a3cdcfa0672d94daedbf0c94686431b816b6c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2673359
Commit-Queue: Martin Šrámek <msramek@chromium.org>
Reviewed-by: Theodore Olsauskas-Warren <sauski@google.com>
Reviewed-by: Rainhard Findling <rainhard@chromium.org>
Reviewed-by: Side YILMAZ <sideyilmaz@chromium.org>
Reviewed-by: Andrey Zaytsev <andzaytsev@google.com>
Reviewed-by: Olesia Marukhno <olesiamarukhno@google.com>
Reviewed-by: Rohit Agarwal <roagarwal@chromium.org>
Reviewed-by: Ehimare Okoyomon <eokoyomon@chromium.org>
Reviewed-by: Bret Sepulveda <bsep@chromium.org>
Reviewed-by: Sean Harrison <harrisonsean@chromium.org>
Cr-Commit-Position: refs/heads/master@{#862454}

tools/traffic_annotation/summary/TRAFFIC_ANNOTATION_OWNERS

@@ -2,7 +2,21 @@
 nicolaso@chromium.org
 
 # Central European Time
+# Please pick a random reviewer:
+#
+# cat tools/traffic_annotation/summary/TRAFFIC_ANNOTATION_OWNERS \
+#   | tail -n+10 | shuf | head -n 1
+#
+andzaytsev@google.com
+bsep@chromium.org
 dullweber@chromium.org
+eokoyomon@chromium.org
+harrisonsean@chromium.org
 mkwst@chromium.org
 msramek@chromium.org
+olesiamarukhno@chromium.org
+rainhard@chromium.org
 rhalavati@chromium.org
+roagarwal@chromium.org
+sauski@google.com
+sideyilmaz@chromium.org