It's very easy to forget to add `require 'rails_helper'` at the top of every core/plugin spec file, and omissions can cause some very confusing/sporadic errors.
By setting this flag in `.rspec`, we can remove the need for `require 'rails_helper'` entirely.
This PR revamps the topic timer UI, using the time shortcut selector from the bookmark modal.
* Fixes an issue where the duration of hours/days after last reply or auto delete replies was not enforced to be > 0
* Fixed an issue where the timer dropdown options were not reloaded correctly if the topic status changes in the background (use `MessageBus` to publish topic state in the open/close timer jobs)
* Moved the duration input and the "based on last post" option from the `future-date-input` component, as it was only used for topic timers. Also moved out the notice that is displayed which was also only relevant for topic timers.
Splits the `ToggleTopicClosed` job into two distinct `OpenTopic` and `CloseTopic` jobs to make the code clearer. The old job cannot be deleted yet because of outstanding sidekiq schedules, so a todo has been added to do so later this year.
Also replaced mentions of `topic_status_update` with `topic_timer` in some files, because the `topic_status_update` model is obsolete and replaced by topic timer.
Added some shortcut methods for checking if a topic is open/whether a user can change an open topic.
