Add status conditions to all objects

[theSuess]

Kubernetes status conditions are the way to go, especially regarding automated healtchecks (see #1444).

While the new alert rule group CR already supports this, we need to implement status conditions for the remaining resources.

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1. Grafana
2. GrafanaFolder
3. GrafanaDashboard
4. GrafanaDatasource

[NissesSenap]

Currently, the other controllers are writing lots of data to statuses to make sure things can get deleted.
If we instead go over to using finalizers, many of these statuses should be able to be removed.

So when wen doing this refactor, I would also consider adding the finalizers to the other controllers.

[theSuess]

I'd tackle it one at a time to keep PRs small and the error potential low. First adding the extra status field and then removing other ones. That way we can also release a version with conditions faster without including breaking changes