Network bug triage: Filter out more bugs from search.

Remove bugs with a comment by
"425761728072-pa1bs18esuhp2cp2qfa1u9vb6p1v6kfu@developer.gserviceaccount.com"
from the filter for finding unlabelled network bugs. These are bugs
reported by FindIt and other related tools. They generally already have
a label attached, and there tend to be rather a lot of them.

Going through 200 bugs titled "x% regression in whatever" isn't terribly
productive, and skipping over them makes it easier to miss user-reported
bugs.

Bug: None
Change-Id: I680691ca987746e219a4edb307d418d7fa0bfede
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1728176Reviewed-by: Eric Roman <eroman@chromium.org>
Commit-Queue: Matt Menke <mmenke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#682832}

net/docs/bug-triage.md

@@ -36,7 +36,7 @@ uniform, predictable two day commitment for all triagers.
 ### Required:
 
 * Identify new network bugs on the bug tracker, looking at [this issue tracker
-  query](https://bugs.chromium.org/p/chromium/issues/list?q=status%3Aunconfirmed&sort=-id&num=1000).
+  query](https://bugs.chromium.org/p/chromium/issues/list?q=status%3Aunconfirmed+-commentby=425761728072-pa1bs18esuhp2cp2qfa1u9vb6p1v6kfu@developer.gserviceaccount.com&sort=-id&num=1000).
 
   * All Unconfirmed issues filed during your triage rotation should be scanned
     for suspected network bugs, a network component assigned and a