[CodeStyle][F401] update flake8 F401 config (unittests/npu,xpu,mlu,ipu) (#46792)

* exclude python code that auto-generated by protoc

* [CodeStyle][F401] update flake8 F401 config (unittests/npu,xpu,mlu,ipu)

* add npu, mlu to `exclude` field

* empty commit, test=document_fix

.flake8

@@ -5,7 +5,15 @@ exclude =
     # A trick to exclude fluid/ but keep fluid/tests/, see more at
     # https://github.com/PaddlePaddle/Paddle/pull/46290#discussion_r976392010
     ./python/paddle/fluid/[!t]**,
-    ./python/paddle/fluid/tra**
+    ./python/paddle/fluid/tra**,
+    # Exclude auto-generated files
+    *_pb2.py,
+    # Exclude third-party libraries
+    ./python/paddle/utils/gast/**,
+    # Exclude files that will be removed in the future, see more at
+    # https://github.com/PaddlePaddle/Paddle/pull/46782#issuecomment-1273033731
+    ./python/paddle/fluid/tests/unittests/npu/**,
+    ./python/paddle/fluid/tests/unittests/mlu/**
 ignore =
     # E, see https://pycodestyle.pycqa.org/en/latest/intro.html#error-codes
     E121,E122,E123,E125,E126,E127,E128,E129,E131,
@@ -60,11 +68,7 @@ per-file-ignores =
     python/paddle/metric/*:F401
     python/paddle/fluid/tests/unittests/ir/*:F401
     python/paddle/fluid/tests/unittests/tokenizer/*:F401
-    python/paddle/fluid/tests/unittests/xpu/*:F401
     python/paddle/fluid/tests/unittests/distribution/*:F401
-    python/paddle/fluid/tests/unittests/mlu/*:F401
-    python/paddle/fluid/tests/unittests/npu/*:F401
-    python/paddle/fluid/tests/unittests/ipu/*:F401
     python/paddle/fluid/tests/unittests/distributed_passes/*:F401
     python/paddle/fluid/tests/unittests/auto_parallel/*:F401
     python/paddle/fluid/tests/unittests/dygraph_to_static/*:F401

.pre-commit-config.yaml

-# Exclude all third-party libraries globally
+# Exclude all third-party libraries and auto-generated files globally
 exclude: |
     (?x)^(
         patches/.+|
         paddle/fluid/framework/fleet/heter_ps/cudf/.+|
         paddle/fluid/distributed/ps/thirdparty/round_robin.h|
-        python/paddle/utils/gast/.+
+        python/paddle/utils/gast/.+|
+        .+_py2\.py|
+        python/paddle/fluid/tests/unittests/npu/.+|
+        python/paddle/fluid/tests/unittests/mlu/.+
     )$
 repos:
 -   repo: https://github.com/Lucas-C/pre-commit-hooks.git