core: define empty securityContext for pods to fix CIS 5.7.3

Resolves CIS benchmark rule 5.7.3, Pods part. SecurityContext
should be explicitly defined in pod level of Pod spec section.
It is sufficient to specify empty securityContext to satisfy
CIS 5.7.3 rule.

5.7.3 Apply Security Context to Your Pods and Containers

When designing your containers and pods, make sure
that you configure the security context for your pods,
containers, and volumes.

Signed-off-by: Peter Razumovsky <prazumovsky@mirantis.com>

pkg/operator/ceph/controller/cleanup.go

@@ -129,6 +129,7 @@ func (c *ResourceCleanup) jobTemplateSpec() v1.PodTemplateSpec {
 			Volumes:            volumes,
 			RestartPolicy:      v1.RestartPolicyOnFailure,
 			PriorityClassName:  cephv1.GetCleanupPriorityClassName(c.cluster.Spec.PriorityClassNames),
+			SecurityContext:    &v1.PodSecurityContext{},
 			ServiceAccountName: k8sutil.DefaultServiceAccount,
 		},
 	}