**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.

, reader(*this)
    , writer(*this)
    , merger_mutator(*this,
        getContext()->getSettingsRef().background_merges_mutations_concurrency_ratio *
        getContext()->getSettingsRef().background_pool_size)
    , merge_strategy_picker(*this)
    , queue(*this, merge_strategy_picker)
    , fetcher(*this)
    , cleanup_thread(*this)
    , part_check_thread(*this)
    , restarting_thread(*this)
    , part_moves_between_shards_orchestrator(*this)
    , allow_renaming(allow_renaming_)
    , replicated_fetches_pool_size(getContext()->getSettingsRef().background_fetches_pool_size)
    , replicated_fetches_throttler(std::make_shared<Throttler>(getSettings()->max_replicated_fetches_network_bandwidth, getContext()->getReplicatedFetchesThrottler()))
    , replicated_sends_throttler(std::make_shared<Throttler>(getSettings()->max_replicated_sends_network_bandwidth, getContext()->getReplicatedSendsThrottler()))
{
    queue_updating_task = getContext()->getSchedulePool().createTask(
        getStorageID().getFullTableName() + " (StorageReplicatedMergeTree::queueUpdatingTask)", [this]{ queueUpdatingTask(); });
    mutations_updating_task = getContext()->getSchedulePool().createTask(
        getStorageID().getFullTableName() + " (StorageReplicatedMergeTree::mutationsUpdatingTask)", [this]{ mutationsUpdatingTask(); });
    merge_selecting_task = getContext()->getSchedulePool().createTask(
        getStorageID().getFullTableName() + " (StorageReplicatedMergeTree::mergeSelectingTask)", [this] { mergeSelectingTask(); });
    
    merge_selecting_task->deactivate();
    mutations_finalizing_task = getContext()->getSchedulePool().createTask(
        getStorageID().getFullTableName() + " (StorageReplicatedMergeTree::mutationsFinalizingTask)", [this] { mutationsFinalizingTask(); });
    if (getContext()->hasZooKeeper() || getContext()->hasAuxiliaryZooKeeper(zookeeper_name))
    {