**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.

{
    return shared->application_type;
}
void Context::setApplicationType(ApplicationType type)
{
    
    shared->application_type = type;
}
void Context::setDefaultProfiles(const Poco::Util::AbstractConfiguration & config)
{
    shared->default_profile_name = config.getString("default_profile", "default");
    getAccessControlManager().setDefaultProfileName(shared->default_profile_name);
    shared->system_profile_name = config.getString("system_profile", shared->default_profile_name);
    setCurrentProfile(shared->system_profile_name);
    applySettingsQuirks(settings, &Poco::Logger::get("SettingsQuirks"));
    shared->buffer_profile_name = config.getString("buffer_profile", shared->system_profile_name);
    buffer_context = Context::createCopy(shared_from_this());
    buffer_context->setCurrentProfile(shared->buffer_profile_name);
}
String Context::getDefaultProfileName() const
{
    return shared->default_profile_name;
}
String Context::getSystemProfileName() const