openshift/manifests: CloudCredential capability for CredentialsRequest

openshift/machine-api-operator@9c20871740 (annotate cloud credentials
request, 2023-11-14, openshift/machine-api-operator#1174) added this
capability to the machine-API analog of this manifest.  And
openshift/cluster-capi-operator@e305541274 (annotate credentials
request manifests, 2023-11-13, openshift/cluster-capi-operator#143)
annotated some cluster-API CredentialsRequests used for other
providers.  This commit catches cluster-API OpenStack up with those
other changes.

There is a risk that tech-preview clusters updating into this change
will have the CloudCredential capability implicitly enabled.  But
because TechPreviewNoUpgrade blocks minor updates, and we don't intend
to backport this to 4.14.z, that exposure is confined to unsuported
prerelease clusters.

openshift/kustomize/credentials-request/credentials-request.yaml

@@ -3,6 +3,8 @@ kind: CredentialsRequest
 metadata:
   name: openshift-cluster-api-openstack
   namespace: openshift-cloud-credential-operator
+  annotations:
+    capability.openshift.io/name: CloudCredential
 spec:
   providerSpec:
     apiVersion: cloudcredential.openshift.io/v1

openshift/manifests/0000_30_cluster-api-provider-openstack_00_credentials-request.yaml

@@ -2,6 +2,7 @@ apiVersion: cloudcredential.openshift.io/v1
 kind: CredentialsRequest
 metadata:
   annotations:
+    capability.openshift.io/name: CloudCredential
     exclude.release.openshift.io/internal-openshift-hosted: "true"
     include.release.openshift.io/self-managed-high-availability: "true"
     release.openshift.io/feature-set: TechPreviewNoUpgrade