Fix upgrade to v0.9 by updating pod readiness gates (#766)

controllers/util/common.go

diff --git a/controllers/util/common.go b/controllers/util/common.go
index 7b2e5c9..0f7fdaa 100644
--- a/controllers/util/common.go
+++ b/controllers/util/common.go
@@ -516,6 +516,12 @@
 		to.Spec.TopologySpreadConstraints = from.Spec.TopologySpreadConstraints
 	}
 
+	if !DeepEqualWithNils(to.Spec.ReadinessGates, from.Spec.ReadinessGates) {
+		requireUpdate = true
+		logger.Info("Update required because field changed", "field", basePath+"Spec.ReadinessGates", "from", to.Spec.ReadinessGates, "to", from.Spec.ReadinessGates)
+		to.Spec.ReadinessGates = from.Spec.ReadinessGates
+	}
+
 	return requireUpdate
 }