Update iOS configuration documentation

permission_handler/README.md

@@ -66,9 +66,11 @@ You must list permission you want to use in your application :
    ```ruby
    post_install do |installer|
      installer.pods_project.targets.each do |target|
-       target.build_configurations.each do |config|
        ... # Here are some configurations automatically generated by flutter
   
+       # Start of the permission_handler configuration
+       target.build_configurations.each do |config|
+   
          # You can enable the permissions needed here. For example to enable camera
          # permission, just remove the `#` character in front so it looks like this:
          #
@@ -123,6 +125,7 @@ You must list permission you want to use in your application :
          ]
   
        end 
+       # End of the permission_handler configuration
      end
    end
    ```