chore(package): update @types/node to version 9.3.0 (#385)

Author: greenkeeper[bot]

package.json

@@ -32,7 +32,7 @@
  "@types/mocha": "^2.2.41",
  "@types/ncp": "^2.0.1",
  "@types/nock": "^9.1.0",
- "@types/node": "^8.0.27",
+ "@types/node": "^9.3.0",
  "@types/once": "^1.4.0",
  "@types/pify": "^3.0.0",
  "@types/proxyquire": "^1.3.28",