fix(package): update yargs to version 12.0.1

Author: greenkeeper[bot]

package.json

@@ -69,7 +69,7 @@
     "jest-config": "^23.0.0",
     "lodash": "^4.17.10",
     "pkg-dir": "^3.0.0",
-    "yargs": "^11.0.0"
+    "yargs": "^12.0.1"
   },
   "peerDependencies": {
     "babel-core": "^6.26.3 || ^7.0.0-0",