Update permission_handler.podspec

ios/permission_handler.podspec

@@ -17,6 +17,6 @@ Permission plugin for Flutter. This plugin provides a cross-platform (iOS, Andro
   s.dependency 'Flutter'
   s.dependency 'Flutter'
   
   
   s.ios.deployment_target = '8.0'
   s.ios.deployment_target = '8.0'
-  s.pod_target_xcconfig = { 'SWIFT_VERSION' => '4.0' }
+  s.pod_target_xcconfig = { 'SWIFT_VERSION' => '4.2' }
 end
 end