api: openstackcluster.status is now optional

When a reconcile loop for the bastion is requeued, we have
this error:
```
OpenStackCluster.infrastructure.cluster.x-k8s.io \"cluster-e2e-rha0r3\" is invalid: ready: Required value"
```

The OpenStackMachine.Status is optional, so let's make the status
optional for openstackcluster too.

api/v1alpha8/openstackcluster_types.go

@@ -167,6 +167,8 @@ type OpenStackClusterSpec struct {
 
 // OpenStackClusterStatus defines the observed state of OpenStackCluster.
 type OpenStackClusterStatus struct {
+	// Ready is true when the cluster infrastructure is ready.
+	// +optional
 	Ready bool `json:"ready"`
 
 	// Network contains information about the created OpenStack Network.

config/crd/bases/infrastructure.cluster.x-k8s.io_openstackclusters.yaml

@@ -5832,6 +5832,7 @@ spec:
                 - name
                 type: object
               ready:
+                description: Ready is true when the cluster infrastructure is ready.
                 type: boolean
               router:
                 description: Router describes the default cluster router
@@ -5905,8 +5906,6 @@ spec:
                 - name
                 - rules
                 type: object
-            required:
-            - ready
             type: object
         type: object
     served: true