**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.

try
    {
        part = get_part();
        if (part->volume->getDisk()->getName() != replaced_disk->getName())
            throw Exception("Part " + part->name + " fetched on wrong disk " + part->volume->getDisk()->getName(), ErrorCodes::LOGICAL_ERROR);
        replaced_disk->removeFileIfExists(replaced_part_path);
        replaced_disk->moveDirectory(part->getFullRelativePath(), replaced_part_path);
    }
    catch (const Exception & e)
    {
        
        
        if (e.code() == ErrorCodes::DIRECTORY_ALREADY_EXISTS)
            return false;
        throw;
    }
    catch (...)
    {
        write_part_log(ExecutionStatus::fromCurrentException());
        throw;
    }
    ProfileEvents::increment(ProfileEvents::ReplicatedPartFetches);
    LOG_DEBUG(log, "Fetched part {} from {}", part_name, source_replica_path);
    return true;
}
void StorageReplicatedMergeTree::startup()
{
    if (is_readonly)
        return;
    try