Upgrade pytest to v6

Author: carver

setup.py

@@ -32,12 +32,12 @@
         "factory-boy==2.11.1",
         "hypothesis>=5,<6",
         "pexpect>=4.6, <5",
-        "pytest>=5.1.3,<6",
+        "pytest>=6.2.4,<7",
         "pytest-asyncio>=0.10.0,<0.11",
         "pytest-cov==2.5.1",
         "pytest-timeout>=1.4.2,<2",
         "pytest-watch>=4.1.0,<5",
-        "pytest-xdist==1.31.0",
+        "pytest-xdist==2.3.0",
     ],
     'lint': [
         "flake8==3.8.2",