operator scc is nor fixed when we define a custom scc with readOnlyRootFilesystem: true

This bug is a backport clone of [Bugzilla Bug 2113973](https://bugzilla.redhat.com/show_bug.cgi?id=2113973). The following is the description of the original bug:
—
If we define a custom scc like this:

allowHostDirVolumePlugin: true
allowHostIPC: false
allowHostNetwork: false
allowHostPID: false
allowHostPorts: false
allowPrivilegeEscalation: false
allowPrivilegedContainer: false
allowedCapabilities: []
apiVersion: security.openshift.io/v1
defaultAddCapabilities: []
fsGroup:
type: MustRunAs
groups:

• system:authenticated
  kind: SecurityContextConstraints
  metadata:
  annotations:
  kubernetes.io/description: MCP Vault Unsealer
  meta.helm.sh/release-name: vault
  meta.helm.sh/release-namespace: mcp-vault
  creationTimestamp: "2022-07-25T11:09:53Z"
  generation: 2
  labels:
  app.kubernetes.io/instance: vault
  app.kubernetes.io/managed-by: Helm
  app.kubernetes.io/name: vault-unsealer
  app.kubernetes.io/version: 3.7.0
  helm.sh/chart: vault-unsealer-3.7.1
  name: vault-unsealer
  resourceVersion: "1793493"
  uid: 6b6d88be-03c0-476d-8602-2e94e4ecfcb5
  priority: null
  readOnlyRootFilesystem: true
  requiredDropCapabilities:
• KILL
• MKNOD
• SETUID
• SETGID
  runAsUser:
  type: RunAsAny
  seLinuxContext:
  type: MustRunAs
  supplementalGroups:
  type: RunAsAny
  users:
• system:serviceaccount:mcp-vault:vault-unsealer
  volumes:
• configMap
• hostPath
• secret

we can see that the pod originally has this scc:

oc get pod machine-config-operator-7f57686f5c-g895k -o yaml | grep scc
openshift.io/scc: hostmount-anyuid

After applying the new SCC ( even if we set a higher priority ) the pod is showing after restart:

oc get pod machine-config-operator-7f57686f5c-jg2jv -o yaml | grep scc
openshift.io/scc: vault-unsealer