Pin reno version to reno!=2.0.0,!=2.3.1,>=1.8.0
Pin sphinx version to sphinx!=1.6.1,>=1.5.1
reno=2.3.1 and sphinx=1.6.1 break releasenotes and doc tests.
Change-Id: I9daab4d970f387ae20ded1bf920ec3b98c7e4597
# This is required for the docs build jobs
-sphinx>=1.5.1 # BSD
+sphinx!=1.6.1,>=1.5.1 # BSD
oslosphinx>=4.7.0 # Apache-2.0
# This is required for the releasenotes build jobs
# FIXME: reno is manually pinned to !=2.0.0 because of bug #1651995
-reno>=1.8.0,!=2.0.0 # Apache-2.0
+reno!=2.0.0,!=2.3.1,>=1.8.0 # Apache-2.0