Update static deps

Author: dmtucker

tox.ini

@@ -156,10 +156,10 @@ commands =
 [testenv:static]
 deps =
     bandit ~= 1.7.0
-    black ~= 20.8b
-    flake8 ~= 3.8.3
+    black ~= 21.6b
+    flake8 ~= 3.9.0
     flake8-commas ~= 2.0.0
-    mypy >= 0.810, < 0.820
+    mypy >= 0.900, < 0.910
 commands =
     black --check src setup.py tests
     flake8 src setup.py tests