`DataTypeFactory::get` locks a mutex inside shared a context, there was a case when many threads were locked inside it

https://pastila.nl/?0043b3e6/c557368f4cf0eb87a3c6f2cc162bc693

It is not clear which thread locked the mutex for a long time. However, it may be possible to lock less inside `DataTypeFactory::get`.
{
    auto lock = getLock();
    return shared->config ? *shared->config : Poco::Util::Application::instance().config();
}
AccessControl & Context::getAccessControl()
{
    return *shared->access_control;
}
const AccessControl & Context::getAccessControl() const
{
    return *shared->access_control;
}
void Context::setExternalAuthenticatorsConfig(const Poco::Util::AbstractConfiguration & config)
{
    auto lock = getLock();
    shared->access_control->setExternalAuthenticatorsConfig(config);
}
std::unique_ptr<GSSAcceptorContext> Context::makeGSSAcceptorContext() const
{
    auto lock = getLock();
    return std::make_unique<GSSAcceptorContext>(shared->access_control->getExternalAuthenticators().getKerberosParams());
}
void Context::setUsersConfig(const ConfigurationPtr & config)
{
    auto lock = getLock();
    shared->users_config = config;
    shared->access_control->setUsersConfig(*shared->users_config);
}
ConfigurationPtr Context::getUsersConfig()