chore: add babel core in playground

Author: devrnt

playground/package.json

@@ -21,6 +21,7 @@
     "scheduler/tracing": "../node_modules/scheduler/tracing-profiling"
   },
   "devDependencies": {
+    "@babel/core": "^7.12.10",
     "@types/react": "^17.0.0",
     "@types/react-dom": "^17.0.0",
     "parcel": "^1.12.4",

playground/yarn.lock

@@ -14,7 +14,7 @@
   resolved "https://registry.yarnpkg.com/@babel/compat-data/-/compat-data-7.12.7.tgz#9329b4782a7d6bbd7eef57e11addf91ee3ef1e41"
   integrity sha512-YaxPMGs/XIWtYqrdEOZOCPsVWfEoriXopnsz3/i7apYPXQ3698UFhS6dVT1KN5qOsWmVgw/FOrmQgpRaZayGsw==
 
-"@babel/core@^7.4.4":
+"@babel/core@^7.12.10", "@babel/core@^7.4.4":
   version "7.12.10"
   resolved "https://registry.yarnpkg.com/@babel/core/-/core-7.12.10.tgz#b79a2e1b9f70ed3d84bbfb6d8c4ef825f606bccd"
   integrity sha512-eTAlQKq65zHfkHZV0sIVODCPGVgoo1HdBlbSLi9CqOzuZanMv2ihzY+4paiKr1mH+XmYESMAmJ/dpZ68eN6d8w==