The most common thing that we do with fab! is:
fab!(:thing) { Fabricate(:thing) }
This commit adds a shorthand for this which is just simply:
fab!(:thing)
i.e. If you omit the block, then, by default, you'll get a `Fabricate`d object using the fabricator of the same name.
We call the `/u/search/users` URL when autocompleting users. It returns
user's name, username and avatar template, but not user ID.
We need it to return user IDs in order to display user status in certain situations.
I could add ID to FoundUserWithStatusSerializer, so it will be added only if
user status is enabled in site settings. But I feel that it's good to always return it,
it's not a lot of data comparing to what we already return, and it should be useful
in other scenarios.
