011ba5b9 slightly changed the way the staff-action-log route is activated. It's now possible for `deserializeQueryParam` to be called with a null value, so we need to deal with that case.
This route is currently untested - we'll follow-up with another commit to add some.
`Route#render` and `Route#renderTemplate` have been deprecated and are removed in Ember 4.x (see: https://deprecations.emberjs.com/v3.x#toc_route-render-template)
The templates of modified routes in this PR are already automatically inserted into `{{outlet}}`s.
