fix(package): update mkdirp to version 1.0.3

Closes #23

Author: greenkeeper[bot]

package.json

@@ -35,7 +35,7 @@
     "diff": "4.0.2",
     "escape-string-regexp": "2.0.0",
     "globby": "10.0.1",
-    "mkdirp": "^0.5.1",
+    "mkdirp": "^1.0.3",
     "pretty-ms": "5.1.0",
     "recursive-copy": "2.0.10",
     "strip-ansi": "6.0.0",