Adding support for DeepNPTS model

[Jonathan-87]

Description

It would be useful to add the Deep Non-Parametric Time Series forecaster (DeepNPTS). You can find the paper here (https://arxiv.org/pdf/2312.14657.pdf) and the model is included in GluonTS. DeepNPTS is a strong baseline and is competitive to complex models.

Use case

No response