How to reproduce:
1. Open project "VfxTest.zip"
2. In the Project window select Folder "Test.vfx"
3. Right-click > Reimport

Expected result: No error
Actual result: Errors appear: "Assertion failed on expression: 'res' UnityEditor.AssetPostprocessingInternal:PostprocessAllAssets (string[],string[],string[],string[],string[],bool)", and "Unknown error occurred while loading 'Assets/Test.vfx'. UnityEditor.AssetPostprocessingInternal:PostprocessAllAssets (string[],string[],string[],string[],string[],bool)"

Reproducible with: 12.0.0 (2021.2.0a6, 2021.2.0b15), 12.1.2 (2021.2.5f1), 13.1.2 (2022.1.0b1)
Not reproducible with: 7.7.1 (2019.4.33f1), 10.7.0 (2020.3.24f1), 11.0.0 (2021.2.0a3), 12.0.0 (2021.2.0a5)

Notes:
- Only reproducible with macOS
- Not reproducible without the Visual Effects Graph package
- In 2021.2.0a1-2021.2.0a5 versions after the 3rd step warnings appear "Importer(DefaultImporter) generated inconsistent result for asset(guid:5d4dd0a41f36a4388b2cd26f14540de8) "Assets/Test.vfx"