UnicodeDecodeError in 06_flyvision_maximally_excitatory_stimuli colab notebook

In [06_flyvision_maximally_excitatory_stimuli.ipynb](https://colab.research.google.com/github/TuragaLab/flyvis/blob/main/examples/06_flyvision_maximally_excitatory_stimuli.ipynb?authuser=4#scrollTo=799b2900), `network_view.optimal_stimulus_responses("T4c")` yields:

<img width="1700" alt="Image" src="https://github.com/user-attachments/assets/6ee36d71-54bb-4638-9055-9472ae059e3f" />