STYLE: upgrade flake8 to version 4+ (pandas-dev#45053)

* update flake repo url and flake version

* bump flake8 and flake8 related dependencies

* revert one of the dependency dumps

* remove cython from flake8 lint

.pre-commit-config.yaml

@@ -35,25 +35,15 @@ repos:
         # we can lint all header files since they aren't "generated" like C files are.
         exclude: ^pandas/_libs/src/(klib|headers)/
         args: [--quiet, '--extensions=c,h', '--headers=h', --recursive, '--filter=-readability/casting,-runtime/int,-build/include_subdir']
--   repo: https://gitlab.com/pycqa/flake8
-    rev: 3.9.2
+-   repo: https://github.com/PyCQA/flake8
+    rev: 4.0.1
     hooks:
     -   id: flake8
         additional_dependencies: &flake8_dependencies
-        - flake8==3.9.2
-        - flake8-comprehensions==3.1.0
+        - flake8==4.0.1
+        - flake8-comprehensions==3.7.0
         - flake8-bugbear==21.3.2
         - pandas-dev-flaker==0.2.0
-    -   id: flake8
-        alias: flake8-cython
-        name: flake8 (cython)
-        types: [cython]
-        args: [--append-config=flake8/cython.cfg]
-    -   id: flake8
-        name: flake8 (cython template)
-        files: \.pxi\.in$
-        types: [text]
-        args: [--append-config=flake8/cython-template.cfg]
 -   repo: https://github.com/PyCQA/isort
     rev: 5.10.1
     hooks:

environment.yml

@@ -20,9 +20,9 @@ dependencies:
   # code checks
   - black=21.5b2
   - cpplint
-  - flake8=3.9.2
+  - flake8=4.0.1
   - flake8-bugbear=21.3.2  # used by flake8, find likely bugs
-  - flake8-comprehensions=3.1.0  # used by flake8, linting of unnecessary comprehensions
+  - flake8-comprehensions=3.7.0  # used by flake8, linting of unnecessary comprehensions
   - isort>=5.2.1  # check that imports are in the right order
   - mypy=0.920
   - pre-commit>=2.9.2

requirements-dev.txt

@@ -8,9 +8,9 @@ asv
 cython>=0.29.24
 black==21.5b2
 cpplint
-flake8==3.9.2
+flake8==4.0.1
 flake8-bugbear==21.3.2
-flake8-comprehensions==3.1.0
+flake8-comprehensions==3.7.0
 isort>=5.2.1
 mypy==0.920
 pre-commit>=2.9.2