There is a slight race in checking of a context deadline exceed in #16467
which leads to a 500 on the repository page.
The solution is to check the error coming back from `*LogNameStatusRepoParser.Next()`
and if it is the `ContextDeadlineExceeded` break from the loop.
Fix#17314
Signed-off-by: Andrew Thornton <art27@cantab.net>