Removed unused shader "2" files that were part of a redesign effort, which is now complete on the development branch. These files are not needed for the upcoming release and could cause confusion for other developers.

ATOM-15837 Remove Unused Shader System Related *2 Classes From Stabilization Branch.

Testing: ASV full test suite on dx12 and vulkan. Only saw known issues.

Gem/Code/Source/RHI/BindlessPrototypeExampleComponent.cpp

@@ -432,8 +432,7 @@ namespace AtomSampleViewer
                 // Take layout of first object
                 pipelineStateDescriptor.m_inputStreamLayout = layout;
 
-                const ShaderVariant& shaderVariant2 = m_shader->GetVariant(RPI::ShaderAsset::RootShaderVariantStableId);
-                shaderVariant2.ConfigurePipelineState(pipelineStateDescriptor);
+                shaderVariant.ConfigurePipelineState(pipelineStateDescriptor);
 
                 RHI::RenderAttachmentLayoutBuilder attachmentsBuilder;
                 attachmentsBuilder.AddSubpass()