unfuck output filename

.gitea/workflows/build.yaml

@@ -27,7 +27,7 @@ jobs:
       - name: build presentation
         working-directory: ./presentation
         run: |
-          npx @marp-team/marp-cli@latest presentation.md --theme-set ./themes -- -o index.html && \
+          npx @marp-team/marp-cli@latest presentation.md -o index.html --theme-set ./themes -- && \
           zip -r ../presentation.zip .
       - name: upload to pages
         run: |