Update dependency mocha to v11

Author: renovate[bot]

package.json

@@ -70,7 +70,7 @@
   "devDependencies": {
     "eslint": "6.8.0",
     "eslint-plugin-ghost": "0.2.0",
-    "mocha": "7.2.0",
+    "mocha": "11.7.5",
     "nyc": "17.1.0",
     "rimraf": "3.0.2",
     "should": "13.2.3",