fix: action lookup stops when matching action has isEnabled set to false

[pathconnected]

Fix site documentation's note on what happens when an action's isEnabled is set to false. The documentation said that search for a matching action continues up in the tree, but it actually stops.

Relevant source code:

• actions.dart#L959-L967
• actions.dart#L873-L882

The maybeFind (second one) is the one used by shortcuts (per shortcuts.dart#L922-L938).

A side example: DismissIntent from modals is handled by _DismissModalAction (routes.dart#L975-L984), and isEnabled is set to false if the modal is not barrierDismissible. Actions that handle the dismiss intent above in the widget tree do not get invoked in that case.

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[flutter-website-bot]

Staged preview of the updated docs.flutter.dev site (updated for commit d6c19e0):

https://flutter-docs-prod--docs-pr13516-fix-intent-bubbling-wh-ncv1bvjb.web.app

[flutter-website-bot]

Staged preview of the updated flutter.dev site (updated for commit d6c19e0):

https://flutter-dev-230821--www-pr13516-fix-intent-bubbling-wh-k728ogi0.web.app