Dragging on iOS prevents further interaction

[gtrafford]

Describe the bug Dragging the sliders on the controls on iOS will move the slider a small amount and then stop. Afterwards no further interaction (pressing or sliding) will move the slider.

To Reproduce Steps to reproduce the behavior:

1. Add a HSLSliders control to NavigationPage(I've tried both TabbedPage and ContentPage, both within a FlyoutPage)
2. Slide the circular slider on the control
3. After releasing (or it stops moving) try sliding it again or pressing elsewhere on the control
4. No further interaction happens

Expected behavior The slider should move to the tapped location, or be able to moved via pressing and sliding

Smartphone (please complete the following information):

• Device: iPhone SE
• OS: iOS 14.8.1
• Version: 1.3.4.21
• Xamarin Forms: 5.0.0.2291

Additional context Also, trying to slide any of the sliders to the right just instead results in the flyout page menu being displayed.