Bump mocha from 3.5.3 to 8.1.2

Bumps [mocha](https://github.com/mochajs/mocha) from 3.5.3 to 8.1.2.
- [Release notes](https://github.com/mochajs/mocha/releases)
- [Changelog](https://github.com/mochajs/mocha/blob/master/CHANGELOG.md)
- [Commits](mochajs/mocha@v3.5.3...v8.1.2)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

package.json

@@ -37,7 +37,7 @@
     "babel-preset-stage-0": "^6.3.13",
     "coveralls": "^3.0.0",
     "istanbul": "^0.4.5",
-    "mocha": "^3.2.0",
+    "mocha": "^8.1.2",
     "nyc": "^10.1.2"
   }
 }