**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.

std::shuffle(replicas.begin(), replicas.end(), thread_local_rng);
    String largest_part_found;
    String largest_replica_found;
    for (const String & replica : replicas)
    {
        if (replica == replica_name)
            continue;
        if (active && !zookeeper->exists(fs::path(zookeeper_path) / "replicas" / replica / "is_active"))
            continue;
        Strings parts = zookeeper->getChildren(fs::path(zookeeper_path) / "replicas" / replica / "parts");
        for (const String & part_on_replica : parts)
        {
            if (part_on_replica == part_name
                || MergeTreePartInfo::contains(part_on_replica, part_name, format_version))
            {
                if (largest_part_found.empty()
                    || MergeTreePartInfo::contains(part_on_replica, largest_part_found, format_version))
                {
                    largest_part_found = part_on_replica;
                    largest_replica_found = replica;
                }
            }
        }
    }
    found_part_name = largest_part_found;
    return largest_replica_found;
}
/** If a quorum is tracked for a part, update information about it in ZK.
  */
void StorageReplicatedMergeTree::updateQuorum(const String & part_name, bool is_parallel)