message: relax generics of PageIterator to simplify it
diff: @@ -28,17 +28,14 @@ where
  /// Iterator that repeatedly calls a function that returns a page until an empty
  /// page is returned.
  -struct PageIterator<T, Request>
  -where
  - Request: Fn(u32, u32) -> ClientResult<Page<T>>,
  -{
  +struct PageIterator<Request> {
  req: Request,
  offset: u32,
  done: bool,
  page_size: u32,
  }
  -impl<T, Request> Iterator for PageIterator<T, Request>
  +impl<T, Request> Iterator for PageIterator<Request>
  where
  Request: Fn(u32, u32) -> ClientResult<Page<T>>,
  {
  