Welcome to the Streamlit community, and thanks for sharing your error log and repo! 
The error ModuleNotFoundError: No module named ‘sklearn’ means your app is trying to use scikit-learn, but it’s not installed in the deployment environment. This usually happens if scikit-learn isn’t listed in your requirements.txt file, or if the file is misnamed or misplaced.
To fix this, add scikit-learn (not sklearn) to your requirements.txt file, save, commit, and push to GitHub. Then redeploy or reboot your app. For more details, see the official docs and community solutions: ModuleNotFoundError No module named - Streamlit Docs, App dependencies - Streamlit Docs, and FAQ: ModuleNotFoundError.
Sources: