chore: release flutter v0.13.2

Pubspec is already updated updated to the correct version, but we've not pushed to Pub yet (probably a mistake).
- Changelog is updated with latest changes
- This PR just fixes some analyzer warnings and is a bit of a formality to make it clear we are releasing to pub

Diffs=
fdd52090d chore: release flutter v0.13.2 (#7100)
89053041a add out of band audio support ios - abstracted audio! (#7079)

Co-authored-by: Gordon <pggordonhayes@gmail.com>

.rive_head

@@ -1 +1 @@
-1460f5366b341ea2535f267c51d589569c870ef7
+fdd52090da92bc230f9bf6d4707a77b1e80e62d2

lib/src/asset.dart

@@ -1,3 +1,5 @@
+// ignore_for_file: deprecated_member_use_from_same_package
+
 import 'package:rive/src/rive_core/assets/file_asset.dart';
 
 export 'package:rive/src/generated/artboard_base.dart';

test/asset_test.dart

@@ -1,3 +1,5 @@
+// ignore_for_file: deprecated_member_use_from_same_package
+
 import 'dart:async';
 import 'dart:io';
 import 'dart:typed_data';

test/mocks/fakes.dart

@@ -1,4 +1,19 @@
 import 'package:flutter_test/flutter_test.dart';
 import 'package:rive/rive.dart';
 
-class ArtboardFake extends Fake implements Artboard {}
+class ArtboardFake extends Fake implements Artboard {
+  bool _isPlaying = true;
+
+  @override
+  bool get isPlaying => _isPlaying;
+
+  @override
+  void pause() {
+    _isPlaying = false;
+  }
+
+  @override
+  void play() {
+    _isPlaying = true;
+  }
+}