Update dependency ember-cli to v4 (#413)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

package.json

@@ -30,7 +30,7 @@
     "@embroider/compat": "1.9.0",
     "@embroider/core": "1.9.0",
     "@embroider/webpack": "1.9.0",
-    "ember-cli": "3.28.6",
+    "ember-cli": "4.8.0",
     "ember-cli-babel": "7.26.11",
     "ember-cli-dependency-checker": "3.3.1",
     "ember-cli-htmlbars": "5.7.2",