Fix outdated comment.

Author: Chris Hellmuth

source/MaterialXTest/MaterialXRenderOsl/Utilities/scene_template_oslcmd.xml

@@ -17,13 +17,7 @@
    </ShaderGroup>
    <Quad corner="-340, -340, -800" edge_x="680, 0, 0" edge_y="0, 680, 0" />
 
-   <!-- Shader graph for routing to output layer:
-   input_shader_parameter_overrides : are parameter overrides for the input shader
-   %input_shader_type% : type of an input shader to feed into the output shader.
-   %input_shader_output% : name of output argument on input shader.
-   %output_shader_type%: type of the output shader used to render with
-   %output_shader_input% : name of input argument on output shader.
-   -->
+   <!-- Shader graph of generated OSL commands. -->
    <ShaderGroup>
       %oslCmd%
    </ShaderGroup>