chore(package): update eslint-plugin-node to version 8.0.0 (#441)

works, no new lint warnings.

package.json

@@ -68,7 +68,7 @@
     "eslint": "^5.0.1",
     "eslint-config-standard": "^12.0.0",
     "eslint-plugin-import": "^2.9.0",
-    "eslint-plugin-node": "^7.0.1",
+    "eslint-plugin-node": "^8.0.0",
     "eslint-plugin-promise": "^4.0.1",
     "eslint-plugin-standard": "^4.0.0",
     "file-loader": "^2.0.0",