**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.

const ASTPtr & partition,
    const StorageMetadataPtr & metadata_snapshot,
    bool attach_part,
    ContextPtr query_context)
{
    assertNotReadonly();
    PartitionCommandsResultInfo results;
    PartsTemporaryRename renamed_parts(*this, "detached/");
    MutableDataPartsVector loaded_parts = tryLoadPartsToAttach(partition, attach_part, query_context, renamed_parts);
    
    ReplicatedMergeTreeSink output(*this, metadata_snapshot, 0, 0, 0, false, false, query_context,
        true);
    for (size_t i = 0; i < loaded_parts.size(); ++i)
    {
        const String old_name = loaded_parts[i]->name;
        output.writeExistingPart(loaded_parts[i]);
        renamed_parts.old_and_new_names[i].first.clear();
        LOG_DEBUG(log, "Attached part {} as {}", old_name, loaded_parts[i]->name);
        results.push_back(PartitionCommandResultInfo{
            .partition_id = loaded_parts[i]->info.partition_id,
            .part_name = loaded_parts[i]->name,
            .old_part_name = old_name,
        });
    }
    return results;
}
void StorageReplicatedMergeTree::checkTableCanBeDropped() const