fix: strip broken /opt/python from PATH, use /usr/bin/python3 explicitly

Author: gounthar

.github/workflows/build-riscv64.yml

@@ -28,10 +28,12 @@ jobs:
 
       - name: Set up Python
         run: |
+          # Remove broken /opt/python from PATH
+          export PATH=$(echo "$PATH" | tr ':' '\n' | grep -v /opt/python | tr '\n' ':' | sed 's/:$//')
           sudo apt-get install -y python3-venv python3-pip python3-dev
-          python3 -m venv --without-pip /tmp/build-venv
+          /usr/bin/python3 -m venv --without-pip /tmp/build-venv
           . /tmp/build-venv/bin/activate
-          curl -sS https://bootstrap.pypa.io/get-pip.py | python3
+          curl -sS https://bootstrap.pypa.io/get-pip.py | /usr/bin/python3
           pip install --upgrade setuptools wheel
 
       - name: Build wheel