chore(deps-dev): update mocha requirement from 6.1.4 to 6.2.0

Updates the requirements on [mocha](https://github.com/mochajs/mocha) to permit the latest version.
- [Release notes](https://github.com/mochajs/mocha/releases)
- [Changelog](https://github.com/mochajs/mocha/blob/master/CHANGELOG.md)
- [Commits](mochajs/mocha@v6.1.4...v6.2.0)

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

package.json

@@ -76,7 +76,7 @@
     "express": "4.17.1",
     "istanbul": "0.4.5",
     "lcov-result-merger": "3.1.0",
-    "mocha": "6.1.4",
+    "mocha": "6.2.0",
     "mocha-lcov-reporter": "1.3.0",
     "nock": "10.0.6",
     "ps-node": "0.1.6",