I want to remove one item from istio virtualservice spec/host list in kubernetes:

kubectl get vs -n test1 projet-b

   apiVersion: networking.istio.io/v1alpha3
    kind: VirtualService
    metadata:
      name: project-b
      namespace: test1
    spec:
      hosts:
      - project-b
      http:
      - match:
        - headers:
            namespace:
              exact: "test2"
        name: test2
        route:
        - destination:
            host: project-b.test2.svc.cluster.local
      - route:
        - destination:
            host: project-b.test1.svc.cluster.local

I would like to remove item name:test in spec/http list