Remove User#internal_attributes method
Remove User#internal_attributes method

It's not needed anymore as we've replaced boolean `support_bot` with
enum `bot_type`.

mmkassem/gitlabhq,mmkassem/gitlabhq,stoplightio/gitlabhq,stoplightio/gitlabhq,iiet/iiet-git,iiet/iiet-git,mmkassem/gitlabhq,stoplightio/gitlabhq,mmkassem/gitlabhq,iiet/iiet-git,stoplightio/gitlabhq,iiet/iiet-git