def split_extras_groups(self, all_groups: list[str]) -> tuple[list[str], list[str]]:
        """Split the groups into extras and non-extras."""
        extras: list[str] = []
        groups: list[str] = []
        optional_groups = {normalize_name(group) for group in self.pyproject.metadata.get("optional-dependencies", [])}
        for group in all_groups:
            if group in optional_groups:
                extras.append(group)
            else:
                groups.append(group)
        return extras, groups
Split the groups into extras and non-extras.
src/pdm/project/core.py