[docs] [issue34293] DOC: Makefile inherits a Sphinx 1.5 bug regarding PAPER envvar

[jfbu]

Change by jfbu <jfbu at free.fr>:


----------
keywords: +patch
pull_requests: +8094
stage:  -> patch review

_______________________________________
Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue34293>
_______________________________________