**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
        {
            shutdown();
        }
        catch (...)
        {
            tryLogCurrentException(__PRETTY_FUNCTION__);
        }
    }
    /** Perform a complex job of destroying objects in advance.
      */
    void shutdown()
    {
        if (shutdown_called)
            return;
        shutdown_called = true;
        Session::shutdownNamedSessions();
        /**  After system_logs have been shut down it is guaranteed that no system table gets created or written to.
          *  Note that part changes at shutdown won't be logged to part log.
          */
        if (system_logs)
            system_logs->shutdown();
        DatabaseCatalog::shutdown();
        if (merge_mutate_executor)
            merge_mutate_executor->wait();
        if (fetch_executor)
            fetch_executor->wait();