chore: update dependency eslint to ^9.21.0

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

Author: renovate[bot]

package-lock.json

@@ -31,7 +31,7 @@
     "@eslint/eslintrc": "^3.3.0",
     "@types/express": "^4.17.21",
     "chai": "^5.2.0",
-    "eslint": "^9.20.1",
+    "eslint": "^9.21.0",
     "eslint-config-loopback": "^13.1.0",
     "eslint-plugin-mocha": "^10.5.0",
     "express": "^4.21.2",