The introduction of the in-memory cache for application settings had a
side effect of making it harder to invalidate changes when the settings
occur. We now bypass the cache because it's possible the admin enabled
the usage ping, and we don't want to annoy the user again if they
already set the value.

To avoid causing significant load on the system, we add an extra check
to ensure the user is an admin. and we don't want to annoy the user
again if they already set the value. This is a bit of hack, but the
alternative would be to put in a more complex cache invalidation
step. Since this call only gets called in the uncommon situation where
the user is an admin and the only user in the instance, this shouldn't
cause too much load on the system.