Enable descheduler by default with RemovePodsViolatingInterPodAntiAffinity plugin

We already discussed about enabling descheduler by default in #1545 (closed), but this has not been implemented.

Since we're not conmfortable of the potential side effects of various descheduler plugins, we should try to configure it with "safe" plugins that evict misplaced pods:

• RemovePodsViolatingInterPodAntiAffinity
• RemovePodsViolatingNodeAffinity

These plugins would allow us to use softAntiAffinity in various places which is putting less constraints during node rolling upgrades without the drawback of having collocated pods as they'll be re-scheduled.