Update dependency mocha to v8.4.0

Author: renovate-bot

package.json

@@ -18,7 +18,7 @@
     "eslint": "7.21.0",
     "eslint-plugin-ghost": "2.0.0",
     "mkdirp": "1.0.4",
-    "mocha": "8.3.0",
+    "mocha": "8.4.0",
     "should": "13.2.3",
     "sinon": "9.2.4"
   },

yarn.lock

@@ -1039,10 +1039,10 @@ mkdirp@^0.5.1, mkdirp@~0.5.1:
   dependencies:
     minimist "^1.2.5"
 
-mocha@8.3.0:
-  version "8.3.0"
-  resolved "https://registry.yarnpkg.com/mocha/-/mocha-8.3.0.tgz#a83a7432d382ae1ca29686062d7fdc2c36f63fe5"
-  integrity sha512-TQqyC89V1J/Vxx0DhJIXlq9gbbL9XFNdeLQ1+JsnZsVaSOV1z3tWfw0qZmQJGQRIfkvZcs7snQnZnOCKoldq1Q==
+mocha@8.4.0:
+  version "8.4.0"
+  resolved "https://registry.yarnpkg.com/mocha/-/mocha-8.4.0.tgz#677be88bf15980a3cae03a73e10a0fc3997f0cff"
+  integrity sha512-hJaO0mwDXmZS4ghXsvPVriOhsxQ7ofcpQdm8dE+jISUOKopitvnXFQmpRR7jd2K6VBG6E26gU3IAbXXGIbu4sQ==
   dependencies:
     "@ungap/promise-all-settled" "1.1.2"
     ansi-colors "4.1.1"