fix(package): update pkg-dir to version 3.0.0

Author: greenkeeper[bot]

package.json

@@ -68,7 +68,7 @@
     "fs-extra": "6.0.1",
     "jest-config": "^23.0.0",
     "lodash": "^4.17.10",
-    "pkg-dir": "^2.0.0",
+    "pkg-dir": "^3.0.0",
     "yargs": "^11.0.0"
   },
   "peerDependencies": {