Use Python 3.9 syntax in tests (#37343)

Signed-off-by: cyy <cyyever@outlook.com>

tests/models/layoutlmv2/test_tokenization_layoutlmv2.py

@@ -1,4 +1,3 @@
-# coding=utf-8
 # Copyright 2021 The HuggingFace Inc. team.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -19,7 +18,6 @@ import re
 import shutil
 import tempfile
 import unittest
-from typing import List
 
 from parameterized import parameterized
 
@@ -295,7 +293,7 @@ class LayoutLMv2TokenizationTest(TokenizerTesterMixin, unittest.TestCase):
                 self.assertEqual([e[0] for e in expected_results], tokens["offset_mapping"])
 
     def test_add_special_tokens(self):
-        tokenizers: List[LayoutLMv2Tokenizer] = self.get_tokenizers(do_lower_case=False)
+        tokenizers: list[LayoutLMv2Tokenizer] = self.get_tokenizers(do_lower_case=False)
         for tokenizer in tokenizers:
             with self.subTest(f"{tokenizer.__class__.__name__}"):
                 special_token = "[SPECIAL_TOKEN]"
@@ -311,7 +309,7 @@ class LayoutLMv2TokenizationTest(TokenizerTesterMixin, unittest.TestCase):
                 self.assertTrue(special_token not in decoded)
 
     def test_add_tokens_tokenizer(self):
-        tokenizers: List[LayoutLMv2Tokenizer] = self.get_tokenizers(do_lower_case=False)
+        tokenizers: list[LayoutLMv2Tokenizer] = self.get_tokenizers(do_lower_case=False)
         for tokenizer in tokenizers:
             with self.subTest(f"{tokenizer.__class__.__name__}"):
                 vocab_size = tokenizer.vocab_size