gh-145587: fix busy loop in multiprocessing.connection.wait on Windows

[Shrey-N]

On Windows, multiprocessing.connection.wait returns immediately if the object_list is empty, regardless of the timeout.

This fix adds a check to make sure the function actually sleeps for the duration of the timeout, matching the Unix behavior and stopping the 100% CPU usage spike.

Verified locally:-

import time
from multiprocessing.connection import wait
start = time.time()
wait([], 1.0) # took 0s before, now takes 1
print(time.time() - start)

Fixes #145587