[25.0] Fix refresh token expiration retrieval logic

[nuwang]

Fixes the following traceback when refresh_token is None:
Oct 31 01:14:47 dev galaxyctl[3357277]: Traceback (most recent call last):
Oct 31 01:14:47 dev galaxyctl[3357277]: File "/mnt/galaxy/galaxy-app/lib/galaxy/authnz/managers.py", line 306, in refresh_expiring_oidc_tokens_for_provider
Oct 31 01:14:47 dev galaxyctl[3357277]: refreshed = backend.refresh(trans, auth)
Oct 31 01:14:47 dev galaxyctl[3357277]: ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Oct 31 01:14:47 dev galaxyctl[3357277]: File "/mnt/galaxy/galaxy-app/lib/galaxy/authnz/psa_authnz.py", line 206, in refresh
Oct 31 01:14:47 dev galaxyctl[3357277]: expires = self._try_to_locate_refresh_token_expiration(user_authnz_token.extra_data)
Oct 31 01:14:47 dev galaxyctl[3357277]: ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Oct 31 01:14:47 dev galaxyctl[3357277]: File "/mnt/galaxy/galaxy-app/lib/galaxy/authnz/psa_authnz.py", line 228, in _try_to_locate_refresh_token_expiration
Oct 31 01:14:47 dev galaxyctl[3357277]: or extra_data["refresh_token"].get("expires", None)
Oct 31 01:14:47 dev galaxyctl[3357277]: ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Oct 31 01:14:47 dev galaxyctl[3357277]: AttributeError: 'NoneType' object has no attribute 'get'

How to test the changes?

(Select all options that apply)

• I've included appropriate automated tests.
• This is a refactoring of components with existing test coverage.
• Instructions for manual testing are as follows:
  1. [add testing steps and prerequisites here if you didn't write automated tests covering all your changes]

License

• I agree to license these and all my past contributions to the core galaxy codebase under the MIT license.

[jdavcs]

Thank you!