Pin Space to Python 3.10 to match locked dependencies

The HF builder defaulted to Python 3.13, but the dependencies are locked for
Python 3.10 (torch 2.5.1, torchvision 0.20.1, etc. have no cp313 wheels),
causing 'No matching distribution found for torchvision==0.20.1'.
Pin python_version so the build uses 3.10 where all wheels exist.

README.md

@@ -5,6 +5,7 @@ colorFrom: green
 colorTo: indigo
 sdk: gradio
 sdk_version: 4.37.2
+python_version: "3.10"
 app_file: app.py
 pinned: false
 hf_oauth: true