Upgrade Parse Server example to use latest Parse Server 5.x

[mtrezza]

Just a small upgrade needed:

• Upgrade to use Parse Server 5.x
• Change engines in package.json use use the same as the version to which Parse Server is upgraded

[parse-github-assistant]

Thanks for opening this issue!

• ❌ Please edit your post and use the provided template when creating a new issue. This helps everyone to understand your post better and asks for essential information to quicker review the issue.

[parseplatformorg]

🎉 This change has been released in version 1.2.0