Update dependency mocha to v8.4.0

Author: renovate-bot

package-lock.json

@@ -11,7 +11,7 @@
     "@wdio/sync": "7.5.7",
     "chai": "4.3.4",
     "chromedriver": "90.0.0",
-    "mocha": "8.3.2",
+    "mocha": "8.4.0",
     "ts-node": "9.1.1",
     "typescript": "4.2.4",
     "wdio-chromedriver-service": "7.0.0"