Fixed broken links to apple human interface guidelines (#13132)

packages/flutter/lib/src/cupertino/activity_indicator.dart

@@ -12,7 +12,7 @@ import 'colors.dart';
 ///
 /// See also:
 ///
-///  * <https://developer.apple.com/ios/human-interface-guidelines/ui-controls/progress-indicators/#activity-indicators>
+///  * <https://developer.apple.com/ios/human-interface-guidelines/controls/progress-indicators/#activity-indicators>
 class CupertinoActivityIndicator extends StatefulWidget {
   /// Creates an iOS-style activity indicator.
   const CupertinoActivityIndicator({

packages/flutter/lib/src/cupertino/button.dart

@@ -42,7 +42,7 @@ const EdgeInsets _kBackgroundButtonPadding = const EdgeInsets.symmetric(
 ///
 /// See also:
 ///
-///  * <https://developer.apple.com/ios/human-interface-guidelines/ui-controls/buttons/>
+///  * <https://developer.apple.com/ios/human-interface-guidelines/controls/buttons/>
 class CupertinoButton extends StatefulWidget {
   /// Creates an iOS-style button.
   const CupertinoButton({
@@ -82,7 +82,7 @@ class CupertinoButton extends StatefulWidget {
   ///
   /// See also:
   ///
-  /// * <https://developer.apple.com/ios/human-interface-guidelines/visual-design/layout/>
+  /// * <https://developer.apple.com/ios/human-interface-guidelines/visual-design/adaptivity-and-layout/>
   final double minSize;
 
   /// The opacity that the button will fade to when it is pressed.

packages/flutter/lib/src/cupertino/dialog.dart

@@ -60,7 +60,7 @@ const BoxDecoration _kCupertinoDialogBackFill = const BoxDecoration(
 ///
 ///  * [CupertinoAlertDialog], which is a dialog with title, contents, and
 ///    actions.
-///  * <https://developer.apple.com/ios/human-interface-guidelines/ui-views/alerts/>
+///  * <https://developer.apple.com/ios/human-interface-guidelines/views/alerts/>
 class CupertinoDialog extends StatelessWidget {
   /// Creates an iOS-style dialog.
   const CupertinoDialog({
@@ -108,7 +108,7 @@ class CupertinoDialog extends StatelessWidget {
 /// See also:
 ///
 ///  * [CupertinoDialog], which is a generic iOS-style dialog.
-///  * <https://developer.apple.com/ios/human-interface-guidelines/ui-views/alerts/>
+///  * <https://developer.apple.com/ios/human-interface-guidelines/views/alerts/>
 class CupertinoAlertDialog extends StatelessWidget {
   /// Creates an iOS-style alert dialog.
   const CupertinoAlertDialog({

packages/flutter/lib/src/cupertino/slider.dart

@@ -31,7 +31,7 @@ import 'thumb_painter.dart';
 ///
 /// See also:
 ///
-///  * <https://developer.apple.com/ios/human-interface-guidelines/ui-controls/sliders/>
+///  * <https://developer.apple.com/ios/human-interface-guidelines/controls/sliders/>
 class CupertinoSlider extends StatefulWidget {
   /// Creates an iOS-style slider.
   ///

packages/flutter/lib/src/cupertino/switch.dart

@@ -44,7 +44,7 @@ import 'thumb_painter.dart';
 /// See also:
 ///
 ///  * [Switch], the material design equivalent.
-///  * <https://developer.apple.com/ios/human-interface-guidelines/ui-controls/switches/>
+///  * <https://developer.apple.com/ios/human-interface-guidelines/controls/switches/>
 class CupertinoSwitch extends StatefulWidget {
   /// Creates an iOS-style switch.
   const CupertinoSwitch({

packages/flutter/lib/src/widgets/bottom_navigation_bar_item.dart

@@ -19,7 +19,7 @@ import 'framework.dart';
 ///  * [BottomNavigationBar]
 ///  * <https://material.google.com/components/bottom-navigation.html>
 ///  * [CupertinoTabBar]
-///  * <https://developer.apple.com/ios/human-interface-guidelines/ui-bars/tab-bars>
+///  * <https://developer.apple.com/ios/human-interface-guidelines/bars/tab-bars>
 class BottomNavigationBarItem {
   /// Creates an item that is used with [BottomNavigationBar.items].
   ///