Refactor upgrade ember 4 (#1501)

Upgrade Ember 4

Co-authored-by: Randall Morey <randall@randallmorey.com>
Co-authored-by: Zhihe Li <zhihe.li@hashicorp.com>

ui/admin/tests/index.html

@@ -2,7 +2,6 @@
 <html>
   <head>
     <meta charset="utf-8">
-    <meta http-equiv="X-UA-Compatible" content="IE=edge">
     <title>Admin Tests</title>
     <meta name="description" content="">
     <meta name="viewport" content="width=device-width, initial-scale=1">