When I browse failed builds in a jobset-eval on Hydra, I regularly
mistake actual build-failures with temporary issues like timeouts (that
probably disappear at the next eval).
To prevent this kind of issue, I figured that using the stopsign-svg for
builds with timeouts or exceeded log-limits is a reasonable choice for
the following reasons:
* A user can now distinguish between actual build-errors (like
compilation-failures or oversized outputs) and (usually) temporary issues
(like a bloated log or a timeout).
* The stopsign is also used for aborted jobs that are shown in a
different tab and can't be confused with timeouts for that reason.