Simplify the way we load and handle CT logs: rather than keeping them
grouped by operator, simply keep a flat list and annotate each log with
its operator's name. At submission time, instead of shuffling operator
groups and submitting to one log from each group, shuffle the whole set
of individual logs.
Support tiled logs by similarly annotating each log with whether it is
tiled or not.
Also make the way we know when to stop getting SCTs more robust.
Previously we would stop as soon as we had two, since we knew that they
would be from different operator groups and didn't care about tiled
logs. Instead, introduce an explicit CT policy compliance evaluation
function which tells us if the set of SCTs we have so far forms a
compliant set.
This is not our desired end-state for CT log submission. Ideally we'd
like to: simplify things even further (don't race all the logs, simply
try to submit to two at a time), improve selection (intelligently pick
the next log to submit to, rather than just a random shuffle), and
fine-tune latency (tiled logs should have longer timeouts than classic
ones). Those improvements will come in future PRs.
Part of https://github.com/letsencrypt/boulder/issues/7872
9102759f4e