**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 default_format.empty() ? "TabSeparated" : default_format;
}
void Context::setDefaultFormat(const String & name)
{
    default_format = name;
}
MultiVersion<Macros>::Version Context::getMacros() const
{
    return shared->macros.get();
}
void Context::setMacros(std::unique_ptr<Macros> && macros)
{
    shared->macros.set(std::move(macros));
}
ContextMutablePtr Context::getQueryContext() const
{
    auto ptr = query_context.lock();
    if (!ptr) throw Exception("There is no query or query context has expired", ErrorCodes::THERE_IS_NO_QUERY);
    return ptr;
}
bool Context::isInternalSubquery() const
{
    auto ptr = query_context.lock();
    return ptr && ptr.get() != this;
}
ContextMutablePtr Context::getSessionContext() const