Sitecore PowerShell Extensions - Update Placeholders

The following script reads all child items under the Home node and changes the placeHolder key as per the per defined mapping (old and new) if the rendering type is "JSON rendering"

references:

1. https://www.kasaku.co.uk/2018/02/28/updating-rendering-placeholders/
2. https://doc.sitecorepowershell.com/