Update dependencies in examples/draft-0-10-0/playground (#2258)

Summary:
This fixes security vulnerabilities detected by github
Pull Request resolved: #2258

Test Plan: Used the example. Everything still works as intended.

Differential Revision: D18690749

Pulled By: mrkev

fbshipit-source-id: 7fd6930023c2baf4ebb66605ca8a96679f94a21a

examples/draft-0-10-0/playground/.env

@@ -0,0 +1 @@
+SKIP_PREFLIGHT_CHECK=true

examples/draft-0-10-0/playground/package.json

@@ -8,16 +8,29 @@
     "draft-js": "file:../../..",
     "immutable": "^3.8.2",
     "react": "^16.2.0",
+    "react-app-polyfill": "^1.0.4",
     "react-codemirror2": "^3.0.7",
     "react-dom": "^16.2.0",
     "react-json-tree": "^0.11.0",
     "react-panelgroup": "^1.0.5",
-    "react-scripts": "^1.1.5"
+    "react-scripts": "3.2.0"
   },
   "scripts": {
     "start": "react-scripts start",
     "build": "react-scripts build",
     "test": "react-scripts test --env=jsdom",
     "eject": "react-scripts eject"
+  },
+  "browserslist": {
+    "production": [
+      ">0.2%",
+      "not dead",
+      "not op_mini all"
+    ],
+    "development": [
+      "last 1 chrome version",
+      "last 1 firefox version",
+      "last 1 safari version"
+    ]
   }
 }

examples/draft-0-10-0/playground/src/index.js

@@ -12,6 +12,8 @@
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 
+import 'react-app-polyfill/ie9'; // For IE 9-11 support
+
 import GkManager from './GkManager';
 import React from 'react';
 import ReactDOM from 'react-dom';