**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.

ops.push_back(zkutil::makeCreateRequest(partition_path, "", zkutil::CreateMode::Persistent));
        
        
        
        ops.push_back(zkutil::makeSetRequest(block_numbers_path, "", -1));
        Coordination::Responses responses;
        Coordination::Error code = zookeeper->tryMulti(ops, responses);
        if (code != Coordination::Error::ZOK && code != Coordination::Error::ZNODEEXISTS)
            zkutil::KeeperMultiException::check(code, ops, responses);
    }
    EphemeralLockInZooKeeper lock;
    
    try
    {
        lock = EphemeralLockInZooKeeper(
            fs::path(partition_path) / "block-", fs::path(zookeeper_table_path) / "temp", *zookeeper, &deduplication_check_ops);
    }
    catch (const zkutil::KeeperMultiException & e)
    {
        if (e.code == Coordination::Error::ZNODEEXISTS && e.getPathForFirstFailedOp() == zookeeper_block_id_path)
            return {};
        throw Exception("Cannot allocate block number in ZooKeeper: " + e.displayText(), ErrorCodes::KEEPER_EXCEPTION);
    }
    catch (const Coordination::Exception & e)
    {
        throw Exception("Cannot allocate block number in ZooKeeper: " + e.displayText(), ErrorCodes::KEEPER_EXCEPTION);
    }
    return {std::move(lock)};
}
Strings StorageReplicatedMergeTree::tryWaitForAllReplicasToProcessLogEntry(