[3.12] gh-130164: Fix inspect.Signature.bind() handling of positional-only args without defaults (GH-130192) (GH-132259)

Follow-up to 9c15202.
(cherry picked from commit dab456dcefd886bde44eb204dc6f1b2f14de0e9d)

Co-authored-by: Jacob Walls <jacobtylerwalls@gmail.com>