Add clean step to workflow

.github/workflows/weblog.yaml

@@ -18,6 +18,10 @@ jobs:
           lfs: false
           token: ${{ gitea.token }}
           fetch: 1
+      - name: Clean 🧹
+        run: bundle exec --no-color jekyll clean -d $OUT_DIR
+        env:
+          OUT_DIR: ${{ secrets.PUB_DIR }}
       - run: echo "Trying to build commit ${{ gitea.ref }} from repository."
       - name: Build ⚙️
         run: bundle exec --no-color jekyll build -d $OUT_DIR