[Landscape] only returns DefaultPhysicalMaterial when run in editor world

Landscape will only return "DefaultPhysicalMaterial" when run in editor world. In game time it will return the proper physical material.

Found in 4.19 CL# 4033788, 4.20 Preview 3 CL# 4135216 , 4.21 CL# 4136834

1. Open attached project
2. Select the BP_physmatscanner actor in the level
3. Press "Get Phys Mat" in the details of the actor
4. Play in editor
5. Press Q

Results:
The returned physical material will show as the default while in editor mode but in game time the correct physical material will be displayed

Expected:
In both editor and game time it would return the same physical material set for each layer