Updated from global requirements

Change-Id: I786194ae5640b3f22cf19375d7917cc96fed5da7

test-requirements.txt

@@ -6,7 +6,7 @@ oslotest>=1.10.0 # Apache-2.0
 testtools>=1.4.0 # MIT
 # These are needed for docs generation
 oslosphinx>=4.7.0 # Apache-2.0
-sphinx>=1.5.1 # BSD
+sphinx!=1.6.1,>=1.5.1 # BSD
 
 coverage!=4.4,>=4.0 # Apache-2.0
 jsonschema!=2.5.0,<3.0.0,>=2.0.0 # MIT