Update dependency ember-cli to v6.9.0

Author: renovate[bot]

package.json

@@ -59,7 +59,7 @@
     "ember-bootstrap": "6.7.0",
     "ember-changeset": "5.0.0",
     "ember-changeset-validations": "5.0.0",
-    "ember-cli": "6.8.1",
+    "ember-cli": "6.9.0",
     "ember-cli-clean-css": "3.0.0",
     "ember-cli-dependency-checker": "3.3.3",
     "ember-cli-deprecation-workflow": "3.4.0",