fix(video_player_avfoundation): update audio track selection for macOS compatibility

- Added macOS 10.13 availability check alongside iOS 11.0
- Updated to use currentMediaSelection property instead of deprecated selectedMediaOptionInMediaSelectionGroup method

Author: nateshmbhat

packages/video_player/video_player_avfoundation/darwin/video_player_avfoundation/Sources/video_player_avfoundation/FVPVideoPlayer.m

@@ -489,8 +489,9 @@ - (nullable FVPNativeAudioTrackData *)getAudioTracks:(FlutterError *_Nullable *_
     NSMutableArray<FVPMediaSelectionAudioTrackData *> *mediaSelectionTracks =
         [[NSMutableArray alloc] init];
     AVMediaSelectionOption *currentSelection = nil;
-    if (@available(iOS 11.0, *)) {
-      currentSelection = [currentItem selectedMediaOptionInMediaSelectionGroup:audioGroup];
+    if (@available(iOS 11.0, macOS 10.13, *)) {
+      AVMediaSelection *mediaSelection = currentItem.currentMediaSelection;
+      currentSelection = [mediaSelection selectedMediaOptionInMediaSelectionGroup:audioGroup];
     } else {
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wdeprecated-declarations"