bpo-45401: Change shouldRollover() methods to only rollover regular f… (GH-28822) (#28867)

…iles.

Also changed some historical return values from 1 -> True and 0 -> False.
(cherry picked from commit 62a667784ba7b84611ebd50fa8a1a464cde32235)

Co-authored-by: Vinay Sajip <vinay_sajip@yahoo.co.uk>

Co-authored-by: Vinay Sajip <vinay_sajip@yahoo.co.uk>