Update demo project

Change-type: patch
Signed-off-by: Stef Kors <stef@balena.io>

Author: StefKors

demo/package.json

@@ -3,10 +3,10 @@
   "version": "0.1.0",
   "private": true,
   "dependencies": {
-    "react": "^16.7.0",
-    "react-dom": "^16.7.0",
-    "react-scripts": "2.1.3",
-    "react-simplemde-editor": "^4.0.0"
+    "react": "16.13.1",
+    "react-dom": "16.13.1",
+    "react-scripts": "^3.4.1",
+    "react-simplemde-editor": "^4.1.0"
   },
   "scripts": {
     "start": "react-scripts start",