Steps to reproduce:

1. Open a URP Project
2. Import the attached asset pack
3. Select all Materials and upgrade the Materials to URP (Edit > Rendering > Materials > Convert Selected Built-in Materials to URP)
4. Observe the Models and Prefabs that use those Materials in the Project Browser

Actual results: The Model and Prefab Previews in the Project Browser still have pink textures even though the Previews in Inspector don't, the Materials have been successfuly upgraded. The Previews update after an Editor restart, they do not update after reimporting the Models and Prefabs. Users have to restart the Editor to work with Assets visually.

Expected results: Previews in the Project Browser that are associated with the upraded Materials are updated and Assets are immediately properly visible

Reproducible with versions: 2022.3.62f1, 6000.0.49f1, 6000.1.4f1, 6000.2.0b2

Tested on (OS): Windows 11

Note: Issue does not reproduce with HDRP Wizard's Material Upgrader