If a user updates a deployment config using Form view instead of yaml, the image pull secret is getting duplicated.
~~~
$ oc get pods ubi9-2-deploy 
        message: |
          error: couldn't assign source annotation to deployment ubi9-2: failed to create manager for existing fields: failed to convert new object (testdc-dup-sec/ubi9-2; /v1, Kind=ReplicationController) to smd typed: .spec.template.spec.imagePullSecrets: duplicate entries for key [name="test-pull-secret"]
        reason: Error
~~~

    4.13.z,4.14.z,4.15.z

    1. Edit DeploymentConfig in Form view
    2. Update image version
    3. Save     

    Issue is not reproducible on OCP 4.16.7+ version.