update pytest to 4.6
also update pytest plugins
@@ -4,13 +4,13 @@ enum34; python_version < '3.4'
freezegun
mock
pretend
-pytest==3.8.2
+# pytest 5.x only supports python 3.5+
+pytest<5.0.0
pytest-cov
-# Prevent installing 7.0 which has install_requires "pytest >= 3.10".
-pytest-rerunfailures<7.0
+# Prevent installing 9.0 which has install_requires "pytest >= 5.0".
+pytest-rerunfailures<9.0
pytest-timeout
-# Prevent installing 1.28.0 which has install_requires "pytest >= 4.4.0".
-pytest-xdist<1.28.0
+pytest-xdist
pyyaml
setuptools>=39.2.0 # Needed for `setuptools.wheel.Wheel` support.
scripttest
