Upper bound pin on setuptools since we're still py2

Author: Baisang

requirements-dev.txt

@@ -10,9 +10,10 @@ tox==3.1.2
 pylint==1.8.2
 pytest-pylint==0.11.0
 pytest-mock==1.10.0
+setuptools<45.0.0
 sphinx-rtd-theme==0.2.4
 mock==2.0.0
 decorator==4.3.0
 tox-pip-extensions==1.2.1
 crc32c==1.7
-py==1.8.0
+py==1.8.0