**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 = tryGetZooKeeper();
    const auto storage_settings_ptr = getSettings();
    res.is_leader = is_leader;
    res.can_become_leader = storage_settings_ptr->replicated_can_become_leader;
    res.is_readonly = is_readonly;
    res.is_session_expired = !zookeeper || zookeeper->expired();
    res.queue = queue.getStatus();
    res.absolute_delay = getAbsoluteDelay(); 
    res.parts_to_check = part_check_thread.size();
    res.zookeeper_path = zookeeper_path;
    res.replica_name = replica_name;
    res.replica_path = replica_path;
    res.columns_version = -1;
    res.log_max_index = 0;
    res.log_pointer = 0;
    res.total_replicas = 0;
    res.active_replicas = 0;
    res.last_queue_update_exception = getLastQueueUpdateException();
    if (with_zk_fields && !res.is_session_expired)
    {
        try
        {
            auto log_entries = zookeeper->getChildren(fs::path(zookeeper_path) / "log");
            if (!log_entries.empty())
            {