config(flake8): Update to latest black formatting suggestion

See also: https://black.readthedocs.io/en/stable/guides/using_black_with_other_tools.html?highlight=compatible#id2

Author: tony

setup.cfg

@@ -3,42 +3,7 @@ exclude = .*/,.tox,*.egg,tmuxp/_compat.py,tmuxp/__*__.py,
 select = E,W,F,N
 max-line-length = 88
 # Stuff we ignore thanks to black: https://github.com/ambv/black/issues/429
-ignore = E111,
-         E121,
-         E122,
-         E123,
-         E124,
-         E125,
-         E126,
-         E201,
-         E202,
-         E203,
-         E221,
-         E222,
-         E225,
-         E226,
-         E227,
-         E231,
-         E241,
-         E251,
-         E261,
-         E262,
-         E265,
-         E271,
-         E272,
-         E302,
-         E303,
-         E306,
-         E502,
-         E701,
-         E702,
-         E703,
-         E704,
-         W291,
-         W292,
-         W293,
-         W391,
-         W503
+extend-ignore = E203
 
 [tool:pytest]
 addopts = --reruns=0