style: ensure trailing newlines

tests/unit/utils/test_ExistingFile.py

@@ -32,4 +32,4 @@ def test_ExistingDirectory(path, expected):
 def test_ExistingDirectory_exceptions(path, expected_exception, expected_exception_message):
     with pytest.raises(expected_exception) as exc_info:
         ExistingFile(path)
-    assert str(exc_info.value) == expected_exception_message
+    assert str(exc_info.value) == expected_exception_message