How to reproduce:
1. Create a new Unity project and install the Visual Effects Graph package
2. Create a new VFX Graph and open it
3. In the "Update Particle" create the "Integration Update: Rotation" block
4. Delete the created block
5. Observe the results

Expected results: No errors are thrown and the VFX Graph can be edited further
Actual results: There are errors after deleting the block and after it no other block can be created

Reproducible with: 2023.3.0a7, 6000.0.36f1, 6000.1.0b4
Not reproducible with: 2022.3.57f1, 2023.3.0a6

Reproducible on: macOS Sequoia 15.1 (M1)
Not reproducible on: No other environment tested

Note: After restarting the project, the Graph is usable again

First lines of the errors:
After deleting:
NullReferenceException: Object reference not set to an instance of an object
UnityEditor.VFX.Block.AngularEulerIntegration+<get_attributes>d__7.MoveNext () (at ./Library/PackageCache/com.unity.visualeffectgraph@eb94083e0420/Editor/Models/Blocks/Implementations/Update/AngularEulerIntegration.cs:19)
System.Linq.Enumerable+SelectEnumerableIterator`2[TSource,TResult].MoveNext () (at <5d2bad5d476f48509d77f299513b2417>:0)
On creating a new block:
ArgumentException: This VisualElement is not my child
UnityEngine.UIElements.VisualElement+Hierarchy.Remove (UnityEngine.UIElements.VisualElement child) (at /Users/bokken/build/output/unity/unity/Modules/UIElements/Core/VisualElementHierarchy.cs:578)