correctly install pillow

Author: charlotrudel

.github/workflows/pylint.yml

@@ -29,9 +29,9 @@ jobs:
         if: steps.changed-files.outputs.any_changed == 'true'
         run: |
           sudo apt-get update
-          sudo apt-get install -y python3-tk pillow
+          sudo apt-get install -y python3-tk
           python -m pip install --upgrade pip
-          pip install pylint
+          pip install pylint pillow
           python -m pip install mypy
 
       - name: Analysing the code with pylint