Refactor Status update calls

[burmanm]

What is missing?

What we want from the code is to keep the CassandraDatacenter Status as descriptive of the state of the reconciliation. However, that has caused a repetition of the same code all over the codebase:

			        dcPatch := client.MergeFrom(dc.DeepCopy())
				if updated := rc.setCondition(api.NewDatacenterCondition(api.DatacenterValid, corev1.ConditionFalse)); updated {
					if err := rc.Client.Status().Patch(rc.Ctx, dc, dcPatch); err != nil {
						rc.ReqLogger.Error(err, "error patching datacenter status for updating")
						return result.Error(err)
					}
				}

While it works, this takes a lot of lines and makes the code look messy (with some silly structural hacks to make Patch happen only once). Instead, the rc.setCondition() should probably do this directly, or even masquerade the NewDatacenterCondition call at the same time. Or do the Status Patching itself on one centralized place, although that could be a lot larger refactoring, so first step could be do to it in the setCondition and then later make that patch happen somewhere else.

Why is this needed?

For easier maintenance.