i18n, vue-router and vuex upgrade

1. Configuration of i18n legacy as false.
2. Translation function t is called using the useI18n.
3. Used the i18n.global.t() function from i18n instead of this.$t()
4. Event bus error that occurred during logout.
5. Implemented vue-router 4.4.0 and vuex upgrade to 4.1.0

Change-Id: I9464d82c76dcc1445ce271983ea3ab9d7b03d265
Signed-off-by: Surya Venkatesan <suryav@ami.com>
diff --git a/src/layouts/AppLayout.vue b/src/layouts/AppLayout.vue
index fa9c212..4f24263 100644
--- a/src/layouts/AppLayout.vue
+++ b/src/layouts/AppLayout.vue
@@ -47,7 +47,7 @@
     this.$root.$on('refresh-application', () => this.refresh());
     setInterval(() => {
       if (!localStorage.getItem('storedUsername')) {
-        this.$eventBus.$consoleWindow.close();
+        this.$eventBus.$consoleWindow?.close();
         this.refresh();
       }
     }, 10000);