feat(cli): add @types/mock-fs dev-dependency

packages/cli/package.json

@@ -114,6 +114,7 @@
     "@types/http-proxy": "^1.17.4",
     "@types/inquirer": "^7.3.1",
     "@types/mini-css-extract-plugin": "^0.9.1",
+    "@types/mock-fs": "^4.13.0",
     "@types/node": "^13.7.2",
     "@types/ora": "^3.2.0",
     "@types/react-dev-utils": "^9.0.4",

yarn.lock

@@ -5206,6 +5206,13 @@
   dependencies:
     "@types/node" "*"
 
+"@types/mock-fs@^4.13.0":
+  version "4.13.0"
+  resolved "https://registry.npmjs.org/@types/mock-fs/-/mock-fs-4.13.0.tgz#b8b01cd2db588668b2532ecd21b1babd3fffb2c0"
+  integrity sha512-FUqxhURwqFtFBCuUj3uQMp7rPSQs//b3O9XecAVxhqS9y4/W8SIJEZFq2mmpnFVZBXwR/2OyPLE97CpyYiB8Mw==
+  dependencies:
+    "@types/node" "*"
+
 "@types/morgan@^1.9.0":
   version "1.9.1"
   resolved "https://registry.npmjs.org/@types/morgan/-/morgan-1.9.1.tgz#6457872df95647c1dbc6b3741e8146b71ece74bf"