Wrong link in 23f_yandex_ml_trainings/homeworks/assignment01_knn/knn_assignment_0_01.ipynb

Instead, this worked for me:
```
'''
If you are using Google Colab, uncomment the next line to download `k_nearest_neighbor.py`. 
You can open and change it in Colab using the "Files" sidebar on the left.
'''
!wget https://raw.githubusercontent.com/girafe-ai/ml-course/23f_yandex_ml_trainings/homeworks/assignment01_knn/k_nearest_neighbor.py
```