Investigate removing `template <typename CommandData>` for `TryAddResponseData`

[tehampson]

It should be possible to use a base class instead of the template "duck-typing" we are using when calling DataModel::Encode(*writer, TLV::ContextTag(CommandDataIB::Tag::kFields), aData).

This will help reduce code compiled code size as well as make code more readable in CommandHandler

Alternative Solution to still explore:

• LambdaBridge as mentioned here