Ica6524895e38e1e54ae3207a1e58a97f53481a12
addressed Sphinx 8.x warnings related to
representing paths as strings
on python 3.9 we clamp sphinx to <8 because
8.0.0 bumps the min python to 3.10
this change bumps the sphinx version check from >= 7.0
to >=8.0 to aling it with the versions we use on py3.9
Change-Id: I62784d7ea2a7c3bee4727bc4bc05d22699f7bbc7
f34b94a1b9