macOS: DS crashes when importing supported and unsupported 3D assets at the same time

Regression to QDS4.5.1

Steps to reproduce:

• Create a 3D project
• Click + in Assets view
• Select attached 3D assets to import
• DS correctly informs that .blend is unsupported file format and cannot be added, but when OK is clicked, DS crashes.
• On windows and Linux crash does not happen but OK button in error dialog cannot be clicked before accepting/cancelling the succeeding import. On macOS order is different -> OK to error dialog needs to be clicked first, before user can accept succeeding import.