suspend fun receiveParameters(): Parameters
RoutingApplicationCall wraps another (inner) call (our Kales call), so we need to unwrap it
and cast it to KalesApplicationCall in order to benefit from the memoized receiveParameters
implementation.
We cannot simply allow users to call RoutingApplicationCall.receiveParameters because that is defined as an extension method, which we cannot override like regular class methods.
Doing that will thus cause ApplicationRequest.receiveChannel to try to read from the stream again, failing to read anyting (because we already did so from DynamicParameterRouteSelector).