Bump eslint from 3.18.0 to 4.18.2

Bumps [eslint](https://github.com/eslint/eslint) from 3.18.0 to 4.18.2.
- [Release notes](https://github.com/eslint/eslint/releases)
- [Changelog](https://github.com/eslint/eslint/blob/master/CHANGELOG.md)
- [Commits](eslint/eslint@v3.18.0...v4.18.2)

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

Author: dependabot[bot]

package.json

@@ -21,7 +21,7 @@
     "chai-as-promised": "^6.0.0",
     "ember-cli": "~3.17.0",
     "ember-cli-release": "1.0.0-beta.2",
-    "eslint": "^3.18.0",
+    "eslint": "^4.18.2",
     "github": "^0.2.4",
     "glob": "^7.1.1",
     "mocha": "^3.2.0",