fix(package): update yargs to version 12.0.1

Author: greenkeeper[bot]

package.json

@@ -19,7 +19,7 @@
   "dependencies": {
     "circular-json": "^0.5.4",
     "debug": "3.1.0",
-    "yargs": "11.0.0"
+    "yargs": "12.0.1"
   },
   "repository": {
     "type": "git",