This replaces `quickSuggestHideSettingsUI` with `quickSuggestSettingsUi`. Like
the old variable, we can show or hide all Suggest settings UI, and now we can
also hide UI that pertains only to Suggest online. This is necessary because as
we start to roll out Suggest to more regions, online (Merino) won't be available
for them initially.
Differential Revision: https://phabricator.services.mozilla.com/D238159
07c0872acb
