gh-142195: Fixed Popen.communicate indefinite loops (GH-143203)

Changed condition to evaluate if timeout is less than or equals to 0. This is needed for simulated time environments such as Shadow where the time will match exactly on the boundary.

---------

Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>