state: Fix segfault on malformed file
Having no TotalBuildTimes along a positive CircuitBuildAbandonedCount count lead to a segfault. We check for that condition and then BUG + log warn if that is the case.
It should never happened in theory but if someone modified their state file, it can lead to this problem so instead of segfaulting, warn.
Fixes #40437 (closed)
Signed-off-by: David Goulet dgoulet@torproject.org