Verified on 4.4.0-0.nightly-2020-04-25-191512 which is upgrade from 4.3.17:
$ oc describe imagepruners.imageregistry.operator.openshift.io
Name:         cluster
Namespace:    
Labels:       <none>
Annotations:  <none>
API Version:  imageregistry.operator.openshift.io/v1
Kind:         ImagePruner
Metadata:
  Creation Timestamp:  2020-04-26T02:19:03Z
  Generation:          1
  Resource Version:    34500
  Self Link:           /apis/imageregistry.operator.openshift.io/v1/imagepruners/cluster
  UID:                 5ff74afc-06ce-414f-8e57-0b5378f86746
Spec:
  Failed Jobs History Limit:      3
  Keep Tag Revisions:             3
  Schedule:                       
  Successful Jobs History Limit:  3
  Suspend:                        true
Status:
  Conditions:
    Last Transition Time:  2020-04-26T02:19:03Z
    Message:               Pruner CronJob has been created
    Reason:                Ready
    Status:                True
    Type:                  Available
    Last Transition Time:  2020-04-26T02:19:03Z
    Message:               Pruner completed successfully
    Reason:                Complete
    Status:                False
    Type:                  Failed
    Last Transition Time:  2020-04-26T02:19:03Z
    Message:               The pruner job has been suspended.
    Reason:                Suspended
    Status:                False
    Type:                  Scheduled
  Observed Generation:     1
Events:                    <none>

I also can see the alert like below: 
$ oc get PrometheusRule -n openshift-image-registry image-registry-operator-alerts -o yaml

  - name: ImagePruner
    rules:
    - alert: ImagePruningDisabled
      annotations:
        message: |
          Automatic image pruning is not enabled. Regular pruning of images
          no longer referenced by ImageStreams is strongly recommended to
          ensure your cluster remains healthy.

          To remove this warning, install the image pruner by creating an
          imagepruner.imageregistry.operator.openshift.io resource with the
          name `cluster`. Ensure that the `suspend` field is set to `false`.
      expr: image_registry_operator_image_pruner_install_status < 2
      labels:
        severity: warning

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2020:0581

I performed an in-place upgrade from 4.3.29 to 4.4.14 (both the latest stable release at the time) and ran into this issue today.