Update flake8 version (#15816)

(cherry picked from commit 1e56b75)

Author: carmocca

.pre-commit-config.yaml

@@ -105,7 +105,7 @@ repos:
           )$
 
   - repo: https://github.com/PyCQA/flake8
-    rev: 4.0.1
+    rev: 6.0.0
     hooks:
       - id: flake8
         name: Check PEP8

setup.cfg

@@ -45,14 +45,6 @@ exclude_lines =
     pass
     rank_zero_warn
     raise NotImplementedError
-# TODO: figure out how to get codecov to pick up the test results on these backends
-#  The actual coverage for each is 90%+
-# *metrics (94%+) are temporarily removed from testing while tests speed up
-omit =
-    pytorch_lightning/cluster_environments/*.py
-    pytorch_lightning/utilities/distributed.py
-    pytorch_lightning/tuner/auto_gpu_select.py
-    pytorch_lightning/distributed/dist.py
 
 
 [flake8]
@@ -72,6 +64,9 @@ verbose = 2
 # https://pep8.readthedocs.io/en/latest/intro.html#error-codes
 format = pylint
 ignore =
-    E731  # Ignore "Do not assign a lambda expression, use a def"
-    W503  # Ignore "Line break occurred before a binary operator"
-    E203  # Ignore "whitespace before ':'"
+    # Ignore "Do not assign a lambda expression, use a def"
+    E731
+    # Ignore "Line break occurred before a binary operator"
+    W503
+    # Ignore "whitespace before ':'"
+    E203