Remove vulkan commandbuffer from Tensor

[axsaucedo]

Currently a tensor owns a comand buffer vulkan object and performs the recordCopy as a command. Initially this was designed as the idea was to avoid exposing the buffer from the tensor itself. The command buffer is also used to create the barrier. However in the case of the barrier, it's possible to just return the barrier itself, and for the case of the recordCopy, it would be possible to just pass the commandbuffer as parameter as opposed to having it as an owned component. This is also important as a tensor shoudl not be bound to a single command buffer.