osd: Invalidate stats during peering if we are rolling a shard forwards.

osd: Invalidate stats during peering if we are rolling a shard forwards.

This change will mean we always recalculate stats upon rolling stats forwards. This prevent the situation where we end up with incorrect statistics due to where we always take the stats of the oldest shard during peering; causing outdated pg stats being applied for cases where the oldest shards are shards that don't see partial writes where num_bytes has changed on other places after that point on that shard.

Signed-off-by: Jon Bailey <jonathan.bailey1@ibm.com>
(cherry picked from commit b178ce476f4a5b2bb0743e36d78f3a6e23ad5506)