inspect.signature should use FORWARDREF annotation_format for python 3.14+

[93578237]

On python 3.14 it fails at least here:
​https://github.com/django/django/blob/13299a6203f4bc3e5b2552c96a51ff2b15da3c43/django/contrib/auth/__init__.py#L43

import typing as t

from django.contrib.auth.backends import ModelBackend


if t.TYPE_CHECKING:
    from django.http import HttpRequest

    from testproject.models import User as UserModel


class AuthenticationBackend(ModelBackend):
    def authenticate(
        self,
        request: HttpRequest | None = None,
        username: str | None = None,
        password: str | None = None,
        **kwargs: t.Any,
    ) -> UserModel | None: ...

Maybe a new function signature should be added to utils/inspect.py