remove unused dep

package.json

@@ -44,7 +44,6 @@
   "dependencies": {},
   "devDependencies": {
     "lerna": "^2.4.0",
-    "mock-stdin": "^0.3.1",
     "npm-run-all": "~4.1.1",
     "tslint": "^5.8.0"
   },

yarn.lock

@@ -4037,10 +4037,6 @@ mocha@~3.5.3:
     mkdirp "0.5.1"
     supports-color "3.1.2"
 
-mock-stdin@^0.3.1:
-  version "0.3.1"
-  resolved "https://registry.npmjs.org/mock-stdin/-/mock-stdin-0.3.1.tgz#c657d9642d90786435c64ca5e99bbd4d09bd7dd3"
-
 modify-values@^1.0.0:
   version "1.0.0"
   resolved "https://registry.npmjs.org/modify-values/-/modify-values-1.0.0.tgz#e2b6cdeb9ce19f99317a53722f3dbf5df5eaaab2"