Update dependency ember-cli to v4

Author: renovate[bot]

package.json

@@ -40,7 +40,7 @@
     "babel-eslint": "10.1.0",
     "broccoli-asset-rev": "3.0.0",
     "ember-auto-import": "2.4.2",
-    "ember-cli": "3.28.5",
+    "ember-cli": "4.6.0",
     "ember-cli-dependency-checker": "3.3.1",
     "ember-cli-inject-live-reload": "2.1.0",
     "ember-cli-htmlbars": "6.1.0",