Currently, when a replica's view update backlog is full, the write is still
sent by the coordinator to all replicas. Because of the backlog, the write
fails on the replica, causing inconsistency that needs to be fixed by repair.
To avoid these inconsistencies, this patch adds a check on the coordinator
for overloaded replicas. As a result, a write may be rejected before being
sent to any replicas and later retried by the user, when the replica is no
longer overloaded.
Fixesscylladb/scylladb#17426
5eaae05aaf