Fix approval-voting canonicalize off by one (#6864)
Approval voting canonicalize is off by one that means if we are finalizing blocks one by one, approval-voting cleans it up every other block for example: - With 1, 2, 3, 4, 5, 6 blocks created, the stored range would be StoredBlockRange(1,7) - When block 3 is finalized the canonicalize works and StoredBlockRange is (4,7) - When block 4 is finalized the canonicalize exists early because of the `if range.0 > canon_number` break clause, so blocks are not cleaned up. - When block 5 is finalized the canonicalize works and StoredBlockRange becomes (6,7) and both block 4 and 5 are cleaned up. The consequences of this is that sometimes we keep block entries around after they are finalized, so at restart we consider this blocks and send them to approval-distribution. In most cases this is not a problem, but in the case when finality is lagging on restart approval-distribution will receive 4 as being the oldest block it needs to work on, and since BlockFinalized is never resent for block 4 after restart it won't get the opportunity to clean that up. Therefore it will end running approval-distribution aggression on block 4, because that is the oldest block it received from approval-voting for which it did not see a BlockFinalized signal. --------- Signed-off-by: Alexandru Gheorghe <[email protected]> (cherry picked from commit 2dd2bb5a)