**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.

ReplicatedFetchList & Context::getReplicatedFetchList() { return shared->replicated_fetch_list; }
const ReplicatedFetchList & Context::getReplicatedFetchList() const { return shared->replicated_fetch_list; }
String Context::resolveDatabase(const String & database_name) const
{
    String res = database_name.empty() ? getCurrentDatabase() : database_name;
    if (res.empty())
        throw Exception("Default database is not selected", ErrorCodes::UNKNOWN_DATABASE);
    return res;
}
String Context::getPath() const
{
    auto lock = getLock();
    return shared->path;
}
String Context::getFlagsPath() const
{
    auto lock = getLock();
    return shared->flags_path;
}
String Context::getUserFilesPath() const
{
    auto lock = getLock();
    return shared->user_files_path;
}
String Context::getDictionariesLibPath() const
{
    auto lock = getLock();
    return shared->dictionaries_lib_path;
}
String Context::getUserScriptsPath() const