Warnings are thrown to the console when deleting a system, and then disabling a block in re-added system

How to reproduce:
1. Create a new VFX and open it
2. Delete Simple Particle System
3. Add Simple Particle System
4. Disable any block

Expected result: No warnings are thrown to the Console
Actual issue: 'Remove 1 owners that couldnt be deserialized from of type UnityEditor.VFX.VFXDataSpawner' and 'Remove 1 linked context(s) that could not be deserialized from Initialize Particle of type UnityEditor.VFX.VFXBasicInitialize' warnings are thrown to the Console

Reproducible with: 2021.2.0a6(11.0.0, 12.0.0)