* [ATOM-15276] Shader Build Pipeline: Add Shader Supervariant System.
Added ShaderAssetBuilder2 & ShaderVariantAssetBuilder2.
Added ShaderAsset2, ShaderVariantAsset2.
Eventually they will be the only builders. AzslBuilder &
SrgLayoutBuilder will be removed.
ShaderResourceGroupAsset will be removed. ShaderAssetBuilder &
ShaderVariantAssetBuilder will be replaced.
Signed-off-by: garrieta <garrieta@amazon.com>