Deep Link Fixes (#1378)

- [x] Fix Android opening the deep link in 3rd party app
- [x] Fix single deep link opening the page multiple times on iOS
- [x] Fix tapping multiple times on the deep link resulting in multiple
pages being opened

app/android/app/src/main/AndroidManifest.xml

@@ -93,7 +93,7 @@
             android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
             android:exported="true"
             android:hardwareAccelerated="true"
-            android:launchMode="singleTop"
+            android:launchMode="singleTask"
             android:theme="@style/LaunchTheme"
             android:windowSoftInputMode="adjustResize">
             <!-- Specifies an Android theme to apply to this Activity as soon as

app/lib/main.dart

@@ -287,7 +287,7 @@ class _DeciderWidgetState extends State<DeciderWidget> {
     _appLinks = AppLinks();
 
     // Handle links
-    _linkSubscription = _appLinks.uriLinkStream.listen((uri) {
+    _linkSubscription = _appLinks.uriLinkStream.distinct().listen((uri) {
       debugPrint('onAppLink: $uri');
       openAppLink(uri);
     });