Update dependency ember-cli to v6.9.1

Author: renovate[bot]

package.json

@@ -57,7 +57,7 @@
     "ember-auto-import": "2.12.0",
     "ember-basic-dropdown": "8.11.0",
     "ember-bootstrap": "6.7.0",
-    "ember-cli": "6.7.2",
+    "ember-cli": "6.9.1",
     "ember-cli-blueprint-test-helpers": "0.19.2",
     "ember-cli-clean-css": "3.0.0",
     "ember-cli-dependency-checker": "3.3.3",