chore: update readme for runtime-test

packages/runtime-test/README.md

@@ -1,16 +1,9 @@
 # @vue/runtime-test
 
 ``` js
-import {
-  h,
-  render,
-  Component,
-  nodeOps,
-  startRecordingOps,
-  dumpOps
-} from '@vue/runtime-test'
+import { h, render, nodeOps, dumpOps } from '@vue/runtime-test'
 
-class App extends Component {
+const App = {
   data () {
     return {
       msg: 'Hello World!'
@@ -23,12 +16,8 @@ class App extends Component {
 
 // root is of type `TestElement` as defined in src/nodeOps.ts
 const root = nodeOps.createElement('div')
-
-startRecordingOps()
-
 render(h(App), root)
 
 const ops = dumpOps()
-
 console.log(ops)
 ```