Description of the problem: MCH stuck in 'Uninstalling' upon deleting the MCH where assisted install has been enabled in MCE

Release version:

Operator snapshot version:
- ACM 2.5.0-DOWNSTREAM-2022-03-01-18-33-27
- MCE 2.0.0-DOWNANDBACK-2022-03-02-01-20-35

OCP version: OCP 4.9.18

Browser Info:

Steps to reproduce:
1. Install ACM + MCH + MCE
2. Create agentServiceConfig object 
3. Delete MCH instance

Actual results:
MCE namespace is stuck in 'Terminating' state which causes MCH deletion hang

Expected results:
MCE + MCH are deleted

Additional info:

1. agentServiceConfig yaml:
apiVersion: agent-install.openshift.io/v1beta1
kind: AgentServiceConfig
metadata:
  name: agent
spec:
  databaseStorage:
    storageClassName: rook-ceph-block
    accessModes:
    - ReadWriteOnce
    resources:
      requests:
        storage: 20Gi
  filesystemStorage:
    storageClassName: rook-ceph-block
    accessModes:
    - ReadWriteOnce
    resources:
      requests:
        storage: 50Gi
  mustGatherImages:
  - name: ocs
    openshiftVersion: '4.9'
    url: registry.redhat.io/ocs4/ocs-must-gather-rhel8
  osImages:
#  - cpuArchitecture: x86_64
#    openshiftVersion: '4.8'
#    rootFSUrl: https://mirror.openshift.com/pub/openshift-v4/dependencies/rhcos/4.8/4.8.2/rhcos-live-rootfs.x86_64.img
#    url: https://mirror.openshift.com/pub/openshift-v4/dependencies/rhcos/4.8/4.8.2/rhcos-4.8.2-x86_64-live.x86_64.iso
#    version: 48.84.202107202156-0
  - cpuArchitecture: x86_64
    openshiftVersion: '4.9'
    rootFSUrl: https://rhcos-redirector.apps.art.xq1c.p1.openshiftapps.com/art/storage/releases/rhcos-4.9/49.84.202110081407-0/x86_64/rhcos-49.84.202110081407-0-live-rootfs.x86_64.img
    url: https://rhcos-redirector.apps.art.xq1c.p1.openshiftapps.com/art/storage/releases/rhcos-4.9/49.84.202110081407-0/x86_64/rhcos-49.84.202110081407-0-live.x86_64.iso
    version: 49.84.202110081407-0


2. MCH status
oc get mch -n ocm
NAME              STATUS         AGE
multiclusterhub   Uninstalling   30m


3. MCE namespace status
oc get ns multicluster-engine
NAME                  STATUS        AGE
multicluster-engine   Terminating   30m

oc get ns multicluster-engine -oyaml
apiVersion: v1
kind: Namespace
metadata:
  annotations:
    openshift.io/sa.scc.mcs: s0:c28,c27
    openshift.io/sa.scc.supplemental-groups: 1000810000/10000
    openshift.io/sa.scc.uid-range: 1000810000/10000
  creationTimestamp: "2022-03-02T18:48:37Z"
  deletionTimestamp: "2022-03-02T19:06:47Z"
  labels:
    kubernetes.io/metadata.name: multicluster-engine
  name: multicluster-engine
  resourceVersion: "152813584"
  uid: 8288ab75-bba8-4b6c-bada-2a363fd3cd40
spec:
  finalizers:
  - kubernetes
status:
  conditions:
  - lastTransitionTime: "2022-03-02T19:07:01Z"
    message: 'Discovery failed for some groups, 1 failing: unable to retrieve the
      complete list of server APIs: admission.agentinstall.openshift.io/v1: the server
      is currently unable to handle the request'
    reason: DiscoveryFailed
    status: "True"
    type: NamespaceDeletionDiscoveryFailure
  - lastTransitionTime: "2022-03-02T19:06:55Z"
    message: All legacy kube types successfully parsed
    reason: ParsedGroupVersions
    status: "False"
    type: NamespaceDeletionGroupVersionParsingFailure
  - lastTransitionTime: "2022-03-02T19:06:55Z"
    message: All content successfully deleted, may be waiting on finalization
    reason: ContentDeleted
    status: "False"
    type: NamespaceDeletionContentFailure
  - lastTransitionTime: "2022-03-02T19:07:01Z"
    message: All content successfully removed
    reason: ContentRemoved
    status: "False"
    type: NamespaceContentRemaining
  - lastTransitionTime: "2022-03-02T19:07:01Z"
    message: All content-preserving finalizers finished
    reason: ContentHasNoFinalizers
    status: "False"
    type: NamespaceFinalizersRemaining
  phase: Terminating


oc get apiservice | grep False
v1.admission.agentinstall.openshift.io                multicluster-engine/agentinstalladmission                    False (ServiceNotFound)   21m


Work-around: Delete the apiservice `v1.admission.agentinstall.openshift.io`