Modify f-oh application to access test server

Change server URL in f-oh app to our test server deployment.

• Change URL as pointed out here: https://gitee.com/westinyang/f-oh#%E9%83%A8%E7%BD%B2%E6%95%99%E7%A8%8B
• Use our test server deployment URL
• Verify app fetches data and can install sample application from server