Dashboards: Changing timezone does not update time range object properly

### What happened? I am trying to write a script that stores the current utcOffset in a dashboard variable, since I need to pass to a query. I am trying to use the Business Text panel for that. When we change the time zone in the dashboard, the time range does not actually change until, the actual times are changed as well. https://github.com/user-attachments/assets/1e07f66b-33d7-4905-8d59-742c9fdf5fcf ### What did you expect to happen? The time range object is updated with the correct selected time zone. ### Did this work before? Don't know. ### How do we reproduce it? See included dashboard JSON. [Time zone mismatch debug-1731072693820.json](https://github.com/user-attachments/files/17679323/Time.zone.mismatch.debug-1731072693820.json) ### Is the bug inside a dashboard panel? I don't think so ### Environment (with versions)? Grafana: 11.3 OS: Windows Browser: Edge ### Grafana platform? Kubernetes ### Datasource(s)? _No response_