* Added updateLastSeen method to user model
refs #10138
* Refactor codebase to use user.updateLastSeen
refs #10138
This is to ensure all updates go via the same method, meaning any
specific logic can be handled in one place, it also helps with grepping
the codebase to find where this occurs
* Created updateUserLastSeen middleware for v2 admin
refs #10138
This is intended to be used with the v2 admin api and _possibly_ the
content api, to give us an accruate report on thelast time a user access
a ghost instance.
* Wired updateUserLastSeen up to v2 Admin API
closes#10138
* Fixed broken test for v2 admin api
no-issue
This test was broken because it was incorrectly testing for a method to
be called exactly once - this was irrelevant to the functionality being
tested for.
* Updated user check method to set status to active
no-issue
* Debounced the updateUserLastSeen middlware an hour
no-issue
* Resolved some PR comments
