Separate CocoaPods imports for MediaEventPrivate header. (#8608)

Author: GabrielMedAlv

source/ios/AdaptiveCards/AdaptiveCards/AdaptiveCards/PrivateHeaders/ACOMediaEventPrivate.h

@@ -5,10 +5,19 @@
 //  Copyright © 2018 Microsoft. All rights reserved.
 //
 
+#ifdef SWIFT_PACKAGE
+/// Swift Package Imports
 #import "ACOMediaEvent.h"
 #import "Media.h"
 #import "MediaSource.h"
 #import "SharedAdaptiveCard.h"
+#else
+/// Cocoapods Imports
+#import <AdaptiveCards/ACOMediaEvent.h>
+#import <AdaptiveCards/Media.h>
+#import <AdaptiveCards/MediaSource.h>
+#import <AdaptiveCards/SharedAdaptiveCard.h>
+#endif
 #import <Foundation/Foundation.h>
 
 using namespace AdaptiveCards;