refactor: reuse SSRContext from server-renderer package

Author: CyberAP

packages/runtime-core/__tests__/hydration.spec.ts

@@ -11,9 +11,8 @@ import {
   defineAsyncComponent,
   defineComponent
 } from '@vue/runtime-dom'
-import { renderToString } from '@vue/server-renderer'
+import { renderToString, SSRContext } from '@vue/server-renderer'
 import { mockWarn } from '@vue/shared'
-import { SSRContext } from 'packages/server-renderer/src/render'
 
 function mountWithHydration(html: string, render: () => any) {
   const container = document.createElement('div')