**Describe the issue**
ClickHouse is unable to start up after upgrading from 20.8 to 21.8. 

There is a replicated table with `:` in zk path and it couldn't be loaded with:

`2021.09.15 03:49:58.435071 [ 633075 ] {} <Error> Application: DB::Exception: Unknown auxiliary ZooKeeper name '/test_prefix'. If it's required it can be added to the section <auxiliary_zookeepers> in config.xml: Cannot attach table `db1`.`table1` from metadata file /var/lib/clickhouse/metadata/db1/table1.sql from query ATTACH TABLE db1.table1 (`field1` String, `date` Date) ENGINE = ReplicatedMergeTree('/test_prefix:db1/{shard}/table1', '{replica}') PARTITION BY toMonth(date) PRIMARY KEY field1 ORDER BY field1 SETTINGS index_granularity = 8192: while loading database `db1` from path /var/lib/clickhouse/metadata/db1
`

**Expected behavior**
ClickHouse server is able to startup after upgrade without schema change. "test_prefix" in "/test_prefix:db1/{shard}/table1" is not interpreted as an auxiliary ZooKeeper name.

}
            auto zookeeper = getZooKeeper();
            
            if (!zookeeper->exists(fs::path(zookeeper_path) / "replicas" / replica / "is_active"))
            {
                LOG_WARNING(log, "Replica {} is not active during mutation. Mutation will be done asynchronously when replica becomes active.", replica);
                inactive_replicas.emplace(replica);
                break;
            }
            String mutation_pointer = fs::path(zookeeper_path) / "replicas" / replica / "mutation_pointer";
            std::string mutation_pointer_value;
            
            if (!zookeeper->tryGet(mutation_pointer, mutation_pointer_value, nullptr, wait_event))
            {
                LOG_WARNING(log, "Replica {} was removed", replica);
                break;
            }
            else if (mutation_pointer_value >= mutation_id) 
                break;                                      
            
            if (wait_event->tryWait(1000))
                continue;
            
            
            auto mutation_status = queue.getIncompleteMutationsStatus(mutation_id);
            
            if (mutation_status && !mutation_status->latest_fail_reason.empty())
                break;
        }