update: podspec

Author: rinov

YoutubeKit.podspec

@@ -11,7 +11,7 @@ DESC
   s.license          = { :type => 'MIT', :file => 'LICENSE' }
   s.author           = { 'rinov' => 'rinov@rinov.jp' }
   s.social_media_url = 'https://twitter.com/rinov0321'
-  s.swift_version = "6.0"
+  s.swift_version = "5.0"
   s.ios.deployment_target = '13.0'
 
   s.source_files = 'YoutubeKit/**/*.swift'