Bump jest from 20.0.4 to 23.6.0

Bumps [jest](https://github.com/facebook/jest) from 20.0.4 to 23.6.0.
- [Release notes](https://github.com/facebook/jest/releases)
- [Changelog](https://github.com/facebook/jest/blob/master/CHANGELOG.md)
- [Commits](jestjs/jest@v20.0.4...v23.6.0)

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

package.json

@@ -18,7 +18,7 @@
  },
  "devDependencies": {
  "fs-extra": "^4.0.2",
- "jest": "^20.0.4",
+ "jest": "^23.6.0",
  "tmp": "^0.0.33"
  },
  "engines": {