chore(package): update mkdirp to version 1.0.4

Closes #50

Author: greenkeeper[bot]

Diff for: package.json

@@ -30,7 +30,7 @@
     "@types/request": "^2.0.8",
     "@types/sequelize": "^4.0.79",
     "chai": "^4.1.2",
-    "mkdirp": "^0.5.1",
+    "mkdirp": "^1.0.4",
     "mocha": "^5.0.0",
     "nyc": "^12.0.1",
     "request": "^2.83.0",