Drop explicit nanobind install

Author: schnellerhase

.github/workflows/pythonapp.yml

@@ -150,7 +150,7 @@ jobs:
       - name: Install dependencies
         run: sudo apt-get install -y libopenblas-dev liblapack-dev ninja-build
       - name: Install Python dependencies
-        run: pip install nanobind scikit-build-core[pyproject]
+        run: pip install scikit-build-core[pyproject]
       - name: Install Basix
         run: pip install --no-build-isolation .