Fix society filter in member achievements

Ghost User
2019-08-14T09:48:21+02:00

Closes #899 #### Previous behaviour 1. Go to [Joren's profile page](https://thalia.nu/members/profile/1239). 1. Notice that "Cooks' Guild" is listed under "ACHIEVEMENTS FOR THALIA" and "SOCIETIES". ### Expected behaviour 1. Go...

Closes #899 (closed)

Previous behaviour

1. Go to Joren's profile page.

2. Notice that "Cooks' Guild" is listed under "ACHIEVEMENTS FOR THALIA" and "SOCIETIES".

Expected behaviour

1. Go to Joren's profile page.

2. Notice that "Cooks' Guild" is listed under "SOCIETIES" only.