Added correct callback to handle the change of shader in our various material editors.

ScriptableRenderPipeline/HDRenderPipeline/Material/Unlit/Editor/BaseUnlitUI.cs

             }
         }
 
+        public override void AssignNewShaderToMaterial(Material material, Shader oldShader, Shader newShader)
+        {
+            base.AssignNewShaderToMaterial(material, oldShader, newShader);
+
+            SetupMaterialKeywordsAndPassInternal(material);
+        }
+
         // This is call by the inspector
         public override void OnGUI(MaterialEditor materialEditor, MaterialProperty[] props)
         {