`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();
    shared->flags_path = path;
}
void Context::setUserFilesPath(const String & path)
{
    auto lock = getLock();
    shared->user_files_path = path;
}
void Context::setDictionariesLibPath(const String & path)