feat(ToggleButton): add sample page

[Arieldelossantos]

GitHub Issue (If applicable): https://github.com/unoplatform/Uno.Gallery/issues/908

PR Type

What kind of change does this PR introduce?

• Feature

What is the current behavior?

No sample page for the ToggleButton control

What is the new behavior?

ToggleButton control included on sample list

PR Checklist

Please check if your PR fulfills the following requirements:

• [x] Tested on iOS.
• [x] Tested on Wasm.
• [x] Tested on Android.
• [x] Tested on UWP.
• [x] Tested in both Light and Dark themes.
• [x] Associated with an issue (GitHub or internal)