test(vue): add multi-version testing (#25785)

packages/vue/test/base/src/App.vue

@@ -0,0 +1,20 @@
+<template>
+  <ion-app>
+    <ion-router-outlet />
+  </ion-app>
+</template>
+
+<script lang="ts">
+import { IonApp, IonRouterOutlet, useIonRouter } from '@ionic/vue';
+import { defineComponent } from 'vue';
+
+export default defineComponent({
+  components: {
+    IonApp,
+    IonRouterOutlet
+  },
+  setup() {
+    (window as any).debugIonRouter = useIonRouter();
+  }
+});
+</script>