Update dependency concurrently to v9 (#92)

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

Author: renovate[bot]

package.json

@@ -48,7 +48,7 @@
     "@glimmer/tracking": "1.1.2",
     "bootstrap": "5.3.8",
     "broccoli-asset-rev": "3.0.0",
-    "concurrently": "8.2.2",
+    "concurrently": "9.2.1",
     "ember-auto-import": "2.10.1",
     "ember-bootstrap": "6.5.0",
     "ember-changeset": "5.0.0",