Bump eslint from 4.19.0 to 4.19.1 in /helpers/npm

Bumps [eslint](https://github.com/eslint/eslint) from 4.19.0 to 4.19.1.
- [Release notes](https://github.com/eslint/eslint/releases)
- [Changelog](https://github.com/eslint/eslint/blob/master/CHANGELOG.md)
- [Commits](eslint/eslint@v4.19.0...v4.19.1)

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

helpers/npm/package.json

@@ -5,7 +5,7 @@
     "semver": "^5.5.0"
   },
   "devDependencies": {
-    "eslint": "^4.19.0",
+    "eslint": "^4.19.1",
     "eslint-plugin-prettier": "^2.6.0",
     "fs-extra": "^5.0.0",
     "jest": "^22.4.2",

helpers/npm/yarn.lock

@@ -1016,9 +1016,9 @@ eslint-visitor-keys@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/eslint-visitor-keys/-/eslint-visitor-keys-1.0.0.tgz#3f3180fb2e291017716acb4c9d6d5b5c34a6a81d"
 
-eslint@^4.19.0:
-  version "4.19.0"
-  resolved "https://registry.yarnpkg.com/eslint/-/eslint-4.19.0.tgz#9e900efb5506812ac374557034ef6f5c3642fc4c"
+eslint@^4.19.1:
+  version "4.19.1"
+  resolved "https://registry.yarnpkg.com/eslint/-/eslint-4.19.1.tgz#32d1d653e1d90408854bfb296f076ec7e186a300"
   dependencies:
     ajv "^5.3.0"
     babel-code-frame "^6.22.0"