Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Author: BitHighlander

tests/test_sign_typed_data.py

@@ -38,7 +38,7 @@ def test_ethereum_sign_typed_data_hash(self):
         self.client.apply_policy("AdvancedMode", 1)
         fixture_path = os.path.join(os.path.dirname(os.path.abspath(__file__)),
                                     'sign_typed_data.json')
-        with open(fixture_path) as f:
+with open(fixture_path, encoding="utf-8") as f:
             txtests = json.load(f)
 
         for test in txtests['tests']: