`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 user_id;
}
void Context::setQuotaKey(String quota_key_)
{
    auto lock = getLock();
    client_info.quota_key = std::move(quota_key_);
}
void Context::setCurrentRoles(const std::vector<UUID> & current_roles_)
{
    auto lock = getLock();
    if (current_roles ? (*current_roles == current_roles_) : current_roles_.empty())
       return;
    current_roles = std::make_shared<std::vector<UUID>>(current_roles_);
    calculateAccessRights();
}
void Context::setCurrentRolesDefault()
{
    auto user = getUser();
    setCurrentRoles(user->granted_roles.findGranted(user->default_roles));
}
boost::container::flat_set<UUID> Context::getCurrentRoles() const
{
    return getRolesInfo()->current_roles;
}
boost::container::flat_set<UUID> Context::getEnabledRoles() const