Add a tutorial for fine-tuning and interpolation

[mtake]

This tutorial aims to guide you through building a model with fine-tuning followed by interpolation.
Based on the tutorial for building a reasoning model, this tutorial has the minimum changes described below.

• Use granite-3.3-8b-instruct as the student model.
• Apply the pre-defined chat template for granite models.
• After fine-tuning, interpolate the last checkpoint with the original student model.

[RobotSail]

Thanks for the contribution @mtake ! LGTM!!