Surface Inputs are not rendering when using the custom BaseShaderGUI

Reproduction steps:
1. Open the attached project "ReproProj"
2. Open the “/Assets/DevDunkStudio/ShadowReceiverURP/Shaders/ShadowReceiver.shadergraph“ in Shader Graph
3. In Graph Settings, change the Custom Editor GUI setting to blank
4. Save Shader Graph
5. Observe the “/Assets/DevDunkStudio/ShadowReceiverURP/Samples/Materials/ShadowReceiverDirectional.mat“ in Inspector
6. Repeat step 2
7. In Graph Settings, change the Custom Editor GUI setting to “CustomShadowQualityInspector“
8. Repeat steps 4 and 5

Expected result: Surface Inputs exist
Actual result: Surface Inputs are not present

Reproducible with: 2022.3.62f1, 6000.0.54f1, 6000.2.0b10, 6000.3.0a2
Could not test with: 6000.1.12f1 (Error in Shader Graph Assets/DevDunkStudio/ShadowReceiverURP/Shaders/ShadowReceiver.shadergraph: Graph is generating too many variants. Either delete Keywords)

Testing environment: Windows 10 Enterprise 21H2
Not reproducible on: No other environment tested

Notes:

• Missing namespace of custom Inspector “DevDunk.ShadowReceiver.Editor.CustomShadowQualityInspector“
• Still reproducible when using DrawSurfaceInputs