Empty lists get turned into nulls on object creation

#### Description:

Not entirely sure if the right repo to raise an issue, but it seems to be a UI glitch to me. When creating an object using property assignment, empty list inputs get converted to `null` - in the example below we should rather get 3 valid objects and ignore 2 empty lists rather than getting 5 objects, 2 of them invalid:

#### Test file(s):

On [SharePoint](https://burohappold.sharepoint.com/sites/BHoM/02_Current/Forms/AllItems.aspx?RootFolder=%2Fsites%2FBHoM%2F02%5FCurrent%2F12%5FScripts%2F01%5FIssue%2FBHoM%2FGrasshopper%5FToolkit%2F%23701%2DCreateObjectFromEmptyList&FolderCTID=0x0120008122C8891F89054B8ACED0196C70DFC4)