Add a description to InstructLab Granite 7b model

[MariaLeonova]

Is your enhancement related to a problem? Please describe

The first and arguably one of the most important models in the catalog has no description:

Describe the solution you'd like

Add a short description about what it does, what the license is, what is the size of the model and other relevant information; potentially linking to Hugging Face for more info.

It has been found, that generally a developer cares about model use cases (text-to-image, speech recognition, etc), model version, what data it has been trained on, usage restrictions and licenses and how it can be user (API URL or similar). We could also consider creating a unified format for all model descriptions based on this ticket outcome.

Describe alternatives you've considered

No response

Additional context

No response

[jeffmaury]

See https://huggingface.co/instructlab/granite-7b-lab