Update dependency @types/mocha to v9

Author: renovate-bot

package.json

@@ -70,7 +70,7 @@
         "@types/eslint-scope": "^3.7.0",
         "@types/eslint-visitor-keys": "^1.0.0",
         "@types/estree": "^0.0.50",
-        "@types/mocha": "^8.0.0",
+        "@types/mocha": "^9.0.0",
         "@types/node": "^14.0.13",
         "@types/request": "^2.48.5",
         "@types/semver": "^7.3.1",