v.21.10Bug Fixes

Multiple Fixes for ClickHouse Keeper Tool

Multiple fixes for the new clickhouse-keeper tool. Fix a rare bug in clickhouse-keeper when the client can receive a watch response before request-response. #28197 (alesapin). Fix incorrect behavior in clickhouse-keeper when list watches (getChildren) triggered with set requests for children. #28190 (alesapin). Fix rare case when changes of clickhouse-keeper settings may lead to lost logs and server hung. #28360 (alesapin). Fix bug in clickhouse-keeper which can lead to endless logs when rotate_logs_interval decreased. #28152 (alesapin).