Fix open (#9368)

utils/check_repo.py

@@ -315,7 +315,7 @@ def find_all_documented_objects():
     """ Parse the content of all doc files to detect which classes and functions it documents"""
     documented_obj = []
     for doc_file in Path(PATH_TO_DOC).glob("**/*.rst"):
-        with open(doc_file) as f:
+        with open(doc_file, "r", encoding="utf-8", newline="\n") as f:
             content = f.read()
         raw_doc_objs = re.findall(r"(?:autoclass|autofunction):: transformers.(\S+)\s+", content)
         documented_obj += [obj.split(".")[-1] for obj in raw_doc_objs]