fix workflow: add tex as dep

.github/workflows/test-paper-notebooks.yml

@@ -22,7 +22,7 @@ jobs:
           python -m pip install --upgrade pip
           python -m pip install -U .
           pip install matplotlib jupyter
-          sudo apt-get install -y pandoc
+          sudo apt-get install -y pandoc texlive-xetex
 
       - name: Run notebooks with nbmake
         run: |