chore(beep boop 🤖): Bump `MCORE_TAG=f682bd0...` (2025-01-04)
🚀 PR to bump `NVIDIA/Megatron-LM` in `Dockerfile.ci` to `MCORE_TAG=f682bd0ee639b04d3d46a3f8f1881a543c7b653d`.  

📝 Please remember the following to-do's before merge: 
- [ ] Verify the presubmit CI  

🙏 Please merge this PR only if the CI workflow completed successfully.