[tests] add the missing require_sacremoses decorator (#29504)

* add sacremoses check

* fix style

* for FlaubertTokenizer

* HerbertTokenizer fix

* add typeHint

* Update src/transformers/testing_utils.py

Co-authored-by: amyeroberts <22614925+amyeroberts@users.noreply.github.com>

* make less skipped

* make quality

* remove import

---------

Co-authored-by: amyeroberts <22614925+amyeroberts@users.noreply.github.com>

src/transformers/testing_utils.py

@@ -90,6 +90,7 @@ from .utils import (
     is_pytest_available,
     is_pytorch_quantization_available,
     is_rjieba_available,
+    is_sacremoses_available,
     is_safetensors_available,
     is_scipy_available,
     is_sentencepiece_available,
@@ -562,6 +563,13 @@ def require_sentencepiece(test_case):
     return unittest.skipUnless(is_sentencepiece_available(), "test requires SentencePiece")(test_case)
 
 
+def require_sacremoses(test_case):
+    """
+    Decorator marking a test that requires Sacremoses. These tests are skipped when Sacremoses isn't installed.
+    """
+    return unittest.skipUnless(is_sacremoses_available(), "test requires Sacremoses")(test_case)
+
+
 def require_seqio(test_case):
     """
     Decorator marking a test that requires SentencePiece. These tests are skipped when SentencePiece isn't installed.