If an asset is referenced using FStringAssetReference::ResolveObject in a blueprint, it cannot be garbage collected

A licensee has reported that using FStringAssetReference::ResolveObject to reference an asset in Blueprints will result in that asset never being garbage collected. Doing the same workflow in C++ does not result in this behavior.

Please note, this only occurs in Standalone Game and packaged games.

Regression?: No
This also occurred in 4.12.5

1. Download the attached project, generate project files, and compile the project
2. Open the project
3. Open the LV_AssetLoad_BP map
4. Start the game in Standalone Game
5. Press Enter to load the asset
   Result: The asset is loaded but, despite not being referenced directly, is never garbage collected.
   Expected: As with the results of the same test but on the LV_AssetLoad_CPP map (all of the same logic but in C++ instead of Blueprints), the asset should be garbage collected a few seconds after being loaded.