Steps to reproduce:
1. Create a new URP project or open an existing one
2. Right-click in Project View
3. Select Create -> Shader Graph -> Blank Shader Graph
4. Open the created shadergraph by double-clicking it
5. In the blackboard click the "+" icon
6. Add two properties (like Float and Color)
7. Add any keyword (Keyword -> Boolean or Enum)
8. Try duplicating the added keyword or copy-paste it to the blackboard

Expected results: Duplicating and copy-pasting works
Actual results: "ArgumentOutOfRangeException: Index must be within the bounds of the List." error is thrown

Reproducible with: ShaderGraph 12.0.0 (2021.2.0b1), 12.1.3 (2021.2.8f1), 13.1.2 (2022.2.0a2), 13.1.3 (2022.1.0b2)
Not reproducible with: ShaderGraph 10.7.0 (2020.3.25f1) 11.0.0 (2021.2.0a1), 12.0.0 (2021.2.0a21) (property and keyword lists seem separated)

Notes:
- Seems like the issue only reproduces when trying to manipulate the last keyword in the blackboard and only if there's at least two properties before it
- Didn't test all of the properties, but doesn't seem like it matters, Float, Color, Cubemap, Matrix4 all can be used to reproduce the issue