Tasks no longer reported to treeherder if reasonCreated is exception

[Gregory Arndt]

A fix went into production and staging for the taskcluster integration
component (mozilla-taskcluster) that reports jobs to Treeherder for
scheduled jobs. This will hopefully reduce some noise for sheriffs.

tl;dr Jobs only scheduled so that they could be resolved as an exception
will not longer appear on Treeherder. These include tasks never scheduled
and their deadline has been exceeded.

Please let me know if you see any issues.

A little longer explanation for those curious:

When a task fails, all dependent tasks are not scheduled and so they do not
appear on Treeherder. However, once their deadline is reached, taskcluster
will schedule a run and resolve it as an exception. This was causing the
tasks to appear in large batches each day as an exception and creating some
noise. When taskcluster creates these runs for the sole purpose of
resolving them as an exception, we create them with a "reasonCreated" as
exception. These type of scenarios are now filtered out by
mozilla-taskcluster and will not be reported to Treeherder. We do log them
in our papertrail logs in case there is ever an issue of why a particular
Task ID is not showing up.


-Greg