*Steps to reproduce:*
# Open any Project
# Create a Shader Graph Asset and double click it to open it
# Delete the Shader Graph Asset in the Project Browser, when prompted confirm to delete the Asset
# When the "Graph removed from project" pop up prompts to recover the Asset choose "Cancel"
# Right click the left over Shader Graph Window and choose "Close Tab"
# When prompted to recover the Asset choose "Cancel" again

*Actual results:* Errors "NullReferenceException: Object reference not set to an instance of an object
UnityEditor.ShaderGraph.GraphData.GetEdges (UnityEditor.Graphing.SlotReference s, System.Collections.Generic.List`1[T] foundEdges) (at ./Library/PackageCache/com.unity.shadergraph@2132c8a97908/Editor/Data/Graphs/GraphData.cs:1311)" are logged in Console

*Expected results:* When choosing the option to "Close Tab" on a Shader Graph Window and the Window has been marked dirty as "(deleted)" the Shader Graph Window and Asset is discarded immediately without a prompt

*Reproducible with versions:* 2022.3.64f1, 6000.0.48f1, 6000.1.8f1, 6000.2.0b7, 6000.3.0a1

*Tested on (OS):* Windows 11