chore(deps): update dependency @types/mocha to v7 (#205)

Co-authored-by: Benjamin E. Coe <[email protected]>

Author: renovate-bot

packages/google-cloud-securitycenter/package.json

@@ -43,7 +43,7 @@
     "google-gax": "^1.14.1"
   },
   "devDependencies": {
-    "@types/mocha": "^5.2.5",
+    "@types/mocha": "^7.0.0",
     "@types/node": "^12.0.0",
     "c8": "^7.0.0",
     "eslint": "^6.0.0",