Allow Ollama Model KeepAlive to be None, defaulting to indefinite (#13059)

Putting this back to `Option<KeepAlive>` to make existing configs keep
working.

Release Notes:

- N/A
53f702c92fKyle Kelley committed on 6/14/2024, 5:33:28 PM· committed by GitHubparentb036533
2 files changedLine totals unavailable