chore: update dependency express to ^4.21.1

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

Author: renovate[bot]

package-lock.json

@@ -32,7 +32,7 @@
     "chai": "^5.1.1",
     "eslint": "^8.57.1",
     "eslint-config-loopback": "^13.1.0",
-    "express": "^4.21.0",
+    "express": "^4.21.1",
     "lockfile-lint": "^4.14.0",
     "mocha": "^10.7.3",
     "supertest": "^7.0.0"