Fix | Support gvk in CLI for policies applied on cluster

[NoSkillGirl]

Signed-off-by: NoSkillGirl singhpooja240393@gmail.com

Related issue

closes #2363

Milestone of this PR

Add the milestone label by commenting /milestone 1.4.3.

What type of PR is this

/kind bug

Proposed Changes

Extracting kind from the policy kinds by string operations.

Proof Manifests

policy.yaml:

apiVersion: kyverno.io/v1
kind: ClusterPolicy
metadata:
  name: container-image-latest
  annotations:
    policies.kyverno.io/owner: Red Hat CoP
    policies.kyverno.io/category: Workload Management
    policies.kyverno.io/description: Check a Deployment is not using the latest tag for their image
spec:
  validationFailureAction: enforce
  rules:
  - name: validate-resources
    match:
      resources:
        kinds:
        - apps/v1/Deployment
    validate:
      message: "{{request.object.kind}}/{{request.object.metadata.name}}: one of its containers is using the latest tag for its image, which is an anti-pattern."
      pattern:
        spec:
          template:
            spec:
              containers:
              - name: "*"
                image: "!*:latest"

apply the following deployment in cluster:

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app.kubernetes.io/name: Foo
  name: imageuseslatesttag
spec:
  replicas: 1
  selector:
    matchLabels:
      app.kubernetes.io/name: Foo
  template:
    metadata:
      labels:
        app.kubernetes.io/name: Foo
    spec:
      containers:
        - name: bar
          image: quay.io/redhat-cop/openshift-applier:latest

Now apply the policy on the deployment:

$ kyverno apply policy.yaml --cluster

Applying 1 policy to 5 resources... 
(Total number of result count may vary as the policy is mutated by Kyverno. To check the mutated policy please try with log level 5)

policy container-image-latest -> resource default/Deployment/imageuseslatesttag failed: 
1. validate-resources: validation error: Deployment/imageuseslatesttag: one of its containers is using the latest tag for its image, which is an anti-pattern. Rule validate-resources failed at path /spec/template/spec/containers/0/image/ 

pass: 4, fail: 1, warn: 0, error: 0, skip: 0 
exit status 1

Checklist

• I have read the contributing guidelines.
• [] I have added tests that prove my fix is effective or that my feature works.
• [] My PR contains new or altered behavior to Kyverno and
  • [] I have added or changed the documentation myself in an existing PR and the link is:
  • [] I have raised an issue in kyverno/website to track the doc update and the link is:
  • [] I have read the PR documentation guide and followed the process including adding proof manifests to this PR.