feat: sidecar-injector to inject kyverno-envoy-plugin as sidecar

[Sanskarzz]

Kyverno-envoy-sidecar Mutating Admission Controller to inject kyverno-envoy-plugin as sidecar .
Till now i have added code which has http server which handle admission review request and patch the sidecar in the requested pod which has label kyverno-envoy-sidecar/injection = enabled
And sidecar container information will be passed via config map like

apiVersion: v1
kind: ConfigMap
metadata:
  name: kyverno-envoy-sidecar
  namespace: sidecar-injector
data:
  sidecars.yaml: |
    - name: kyverno-envoy-sidecar
      containers:
      - image: sanskardevops/plugin:0.0.25
        imagePullPolicy: IfNotPresent
        name: ext-authz
        ports:
        - containerPort: 8000
        - containerPort: 9000
        args:
        - "serve"
        - "--policy=/policies/policy.yaml"
        volumeMounts:
        - name: policy-files
          mountPath: /policies
      volumes:
      - name: policy-files
        configMap:
          name: policy-files
      

Till now what is done

• An https server or webhook server to handle AdmissionReview object and patch the sidecar configurations
• Containerization of the https server with Docker
• Add Deployment and mutating Admission webhook configurations manifests for installation of the kyverno envoy sidecar injector
• Add example manifest to test
• README.md for better installtion of the kyverno envoy sidecar and for this admission controller works