Add "Query advanced CSOM properties with PnP PowerShell" sample

[jackpoz]

This sample script shows how to query CSOM properties with PnP PowerShell by writing C# code, importing it in PowerShell and sending a single Invoke-PnPQuery request, useful when trying to speed up scripts that have to process a lot of site collections where every request affects the execution time.

I have used this method went writing inventory scripts with 10'000+ site collections (and I wish I knew about it when I had 300'000 site collections :P )

Closes https://github.com/pnp/script-samples/issues/687

Still unsure about the sample.json and preview.png, hope it's good enough :)