[Calling][Bug] Hide the more list if no button is visible

[ShaunaSong]

Purpose

• Update the demo app to hide all the buttons
• Refactor the control bar to make sure if no button is visible, hide the more list button

Does this introduce a breaking change?

• [ ] Yes
• [x] No

Pull Request Type

What kind of change does this Pull Request introduce?

• [ ] Bugfix
• [ ] Feature
• [ ] Code style update (formatting, local variables)
• [ ] Refactoring (no functional changes, no api changes)
• [ ] Documentation content changes
• [ ] Other... Please describe:

Pull request checklist

This PR has considered:

• [ ] Color Theming
• [ ] iOS supported versions (all major versions greater than or equal current target deployment version)
• [ ] VoiceOver and Keyboard Accessibility
• [ ] Internationalization and Right to Left layouts
• [ ] Size classes and window sizes (iPhone vs iPad, notched devices, multitasking, different window sizes, etc)
• [ ] View Data Injection
• [ ] Demo App UI/UX update

How to Test

• Open...
• Click on...

What to Check

Before	After
Screenshot or description before this change	Screenshot or description with this change

Other Information