fix(ci): upgrade nodemon to ^3 to resolve semver ReDoS vulnerability

nodemon@2 depends on simple-update-notifier which depends on a
vulnerable range of semver (7.0.0-7.5.1, GHSA-c2qf-rxjj-qqgw).
Upgrading to nodemon@3 pulls in a clean dependency tree.
npm audit now reports 0 vulnerabilities.

package.json

@@ -21,7 +21,7 @@
   },
   "devDependencies": {
     "concurrently": "^7.6.0",
-    "nodemon": "^2.0.22"
+    "nodemon": "^3.1.14"
   },
   "keywords": [
     "sabnzbd",