Remove attr_accessible from TopicSuggestion
Remove attr_accessible from TopicSuggestion

In order to convert this to strong parameters we'd need to filter the
parameters for the whole edition form, which whilst worth doing, isn't
something we want to tackle as part of this work.

ggoral/whitehall,alphagov/whitehall,hotvulcan/whitehall,askl56/whitehall,YOTOV-LIMITED/whitehall,YOTOV-LIMITED/whitehall,YOTOV-LIMITED/whitehall,ggoral/whitehall,robinwhittleton/whitehall,robinwhittleton/whitehall,askl56/whitehall,alphagov/whitehall,ggoral/whitehall,YOTOV-LIMITED/whitehall,robinwhittleton/whitehall,hotvulcan/whitehall,ggoral/whitehall,askl56/whitehall,alphagov/whitehall,robinwhittleton/whitehall,alphagov/whitehall,hotvulcan/whitehall,askl56/whitehall,hotvulcan/whitehall