chore(package): update commitizen to version 3.1.2

Closes #179

Author: greenkeeper[bot]

package.json

@@ -89,7 +89,7 @@
     "@types/prompts": "1.2.0",
     "@types/webpack-config-utils": "2.3.0",
     "brotli-size": "0.0.3",
-    "commitizen": "3.0.5",
+    "commitizen": "3.1.2",
     "cross-var": "1.1.0",
     "cz-conventional-changelog": "2.1.0",
     "gzip-size": "5.0.0",