update EnvoyFilter testdata (#3584)

Author: zirain

tests/testdata/envoyfilter-valid.yaml

@@ -12,6 +12,8 @@ spec:
             name: "envoy.filters.network.http_connection_manager"
             subFilter:
               name: "envoy.filters.http.router"
+      patch:
+        operation: REMOVE
 ---
 apiVersion: networking.istio.io/v1alpha3
 kind: EnvoyFilter
@@ -23,6 +25,8 @@ spec:
       match:
         context: WAYPOINT
         waypoint: {}
+      patch:
+        operation: REMOVE
 ---
 apiVersion: networking.istio.io/v1alpha3
 kind: EnvoyFilter