fix(package): update @types/node to version 12.0.6

Closes #31

Author: greenkeeper[bot]

package.json

@@ -62,7 +62,7 @@
     "@commitlint/config-conventional": "^7.3.1",
     "@types/enzyme": "^3.1.15",
     "@types/jest": "^24.0.0",
-    "@types/node": "^11.11.7",
+    "@types/node": "^12.0.6",
     "babel-plugin-auto-import": "^1.0.5",
     "coveralls": "^3.0.3",
     "css-loader": "^2.1.1",