Extend the PowerShell scripts Get-PowerBIReport and Export-PowerBIReport to identify RDL vs PBIX content

The current PowerShell scripts for Get-PowerBIReport and Export-PowerBIReport don't appear to have any way to identify RDL vs PBIX content. Would like to be able to place the correct extension on files during scripted extraction processes, rather than a manual review and reassignment based on file content after the fact. Thanks!