Remove `model-` from tag name

## Description

https://github.com/elimu-ai/model/tags

## Why?

Including the artifact ID in the tag version is not necessary.

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> elimu.ai's mission is to build innovative learning software that empowers out-of-school children to teach themselves basic reading📖, writing✍🏽 and math🔢 **within 6 months**.