Correctly implement the UIGestureRecognizer state machine

[filipnavara]

Description of Change

Apple has an extensive documentation on implementing custom gesture recognizers. For discrete gesture recognizers, like the one implemented in TouchBehavior, you are supposed to communicate the state back as Possible / Failure / Recognized. This affects interaction with other gesture recognizers.

Previously the State was never set and left at the default Possible value (initial value and default after Reset). This causes simultaneous gesture recognizers on parent views to fire even if TouchBehavior recognized the gesture.

As a side effect of fixing the state machine, we no longer need to manually prevent simultaneous touches with ShouldReceiveTouch behavior override and we can revert ShouldRecognizeSimultaneously to its default behavior of returning false.

Linked Issues

PR Checklist

• Has a linked Issue, and the Issue has been approved(bug) or Championed (feature/proposal)
• Has tests (if omitted, state reason in description)
• Has samples (if omitted, state reason in description)
• Rebased on top of main at time of PR
• Changes adhere to coding standard
• Documentation created or updated: https://github.com/MicrosoftDocs/CommunityToolkit/pulls

Additional information