Based on the Taskcluster log for
(https://taskcluster-artifacts.net/HkxDh1oKQceXH1fL9RSGow/0/public/logs/live_backing.log),
it looks like the job is running successfully but hitting the max time limit.

Our builds + tests shouldn't take this long to run normally,
but we'll need to set up sccache with cache uploading/downloading
in order to improve most build times.

For now, bump the max run time to 2 hours;
since we complete one build + som tests within an hour,
2 hours should be enough for the second build to finish as well.