do not block rolling updates with lazy spilo update enabled (zalando#1012)

* do not block rolling updates with lazy spilo update enabled

* treat initContainers like Spilo image

Co-authored-by: Felix Kunde <[email protected]>

Author: FxKu

docs/reference/operator_parameters.md

@@ -76,7 +76,7 @@ Those are top-level keys, containing both leaf keys and groups.
   The default is `true`.
 
 * **enable_lazy_spilo_upgrade**
-  Instruct operator to update only the statefulsets with the new image without immediately doing the rolling update. The assumption is pods will be re-started later with the new image, for example due to the node rotation.
+  Instruct operator to update only the statefulsets with new images (Spilo and InitContainers) without immediately doing the rolling update. The assumption is pods will be re-started later with new images, for example due to the node rotation.
   The default is `false`.
 
 * **etcd_host**

pkg/cluster/cluster.go

@@ -488,7 +488,6 @@ func (c *Cluster) compareStatefulSetWith(statefulSet *appsv1.StatefulSet) *compa
 	// until they are re-created for other reasons, for example node rotation
 	if c.OpConfig.EnableLazySpiloUpgrade && !reflect.DeepEqual(c.Statefulset.Spec.Template.Spec.Containers[0].Image, statefulSet.Spec.Template.Spec.Containers[0].Image) {
 		needsReplace = true
-		needsRollUpdate = false
 		reasons = append(reasons, "lazy Spilo update: new statefulset's pod image doesn't match the current one")
 	}