API: Always request page_is_redirect from ApiQueryInfo

The ApiPageSet doesn't know for sure whether it will be resolving
redirects until it is executed, as the revids parameter may override
that (and it can't easily check before being executed because it might
never actually be executed). So ApiQueryInfo needs to just
unconditionally request page_is_redirect and only consider later whether
to try using it.

Bug: 73464
Change-Id: I2297158188dae5476c5b9b5755ea26cf5b8ae487