**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.

break;
        }
        else if (rc == Coordination::Error::ZBADVERSION)
        {
            if (results[0]->error != Coordination::Error::ZOK)
                throw Exception("Metadata on replica is not up to date with common metadata in Zookeeper. It means that this replica still not applied some of previous alters."
                                " Probably too many alters executing concurrently (highly not recommended). You can retry this error",
                    ErrorCodes::CANNOT_ASSIGN_ALTER);
            
            if (query_context->getZooKeeperMetadataTransaction())
                throw Exception("Cannot execute alter, because mutations version was suddenly changed due to concurrent alter",
                                ErrorCodes::CANNOT_ASSIGN_ALTER);
            continue;
        }
        else
        {
            throw Coordination::Exception("Alter cannot be assigned because of Zookeeper error", rc);
        }
    }
    table_lock_holder.unlock();
    LOG_DEBUG(log, "Updated shared metadata nodes in ZooKeeper. Waiting for replicas to apply changes.");
    waitForLogEntryToBeProcessedIfNecessary(*alter_entry, query_context, "Some replicas doesn't finish metadata alter: ");
    if (mutation_znode)
    {
        LOG_DEBUG(log, "Metadata changes applied. Will wait for data changes.");
        waitMutation(*mutation_znode, query_context->getSettingsRef().replication_alter_partitions_sync);
        LOG_DEBUG(log, "Data changes applied.");
    }
}
String getPartNamePossiblyFake(MergeTreeDataFormatVersion format_version, const MergeTreePartInfo & part_info)