Reduce unnecessary logging in frontend

[SiAdcock]

We log more than is necessary in frontend, which has a number of downsides:

• it becomes difficult to distinguish real errors from noise. We must then spend time investigating large numbers of errors in applications such as application, discussion and sport
• it's causing issues for DevX as the amount of logging space is limited

If we go through applications that log more than others, we should be able to identify and eliminate unnecessary logging calls, and define rules around when we ought to be logging.

See also: https://docs.google.com/document/d/1CHvf699hs_rY0e8TkSUuuLNgjrb4nlbAR9SG-Be6bc4