Do not use separaate repo.

.github/workflows/user-requested-benchmark.yml

@@ -44,31 +44,23 @@ jobs:
           ./runner/collect_results.py latest latest-benchmark-results.csv
         shell: bash
 
-      - name: Checkout repository for saving graphics
-        uses: actions/checkout@v2
-        with:
-          token: ${{ secrets.GITHUB_TOKEN }}
-          repository: lf-lang/benchmarks-lingua-franca
-          ref: graphics
-          path: graphics-repo
-          fetch-depth: 0  # History is required for push
-
       - name: Make figure
         run: |
           OUTPUT_DIR=runner/images/$(date -I)
           SHA=${{ github.sha }}
           OUTPUT_FILE=$OUTPUT_DIR/${SHA:0:7}.png
-          mkdir -p graphics-repo/$OUTPUT_DIR
-          ./runner/make-graphics.py latest-benchmark-results.csv graphics-repo/$OUTPUT_FILE
+          mkdir -p $OUTPUT_DIR
+          ./runner/make-graphics.py latest-benchmark-results.csv $OUTPUT_FILE
           echo "::set-output name=output_file::$OUTPUT_FILE"
         shell: bash
         id: figure
 
       - name: Commit figure
         run: |
-          cd graphics-repo
           git config --global user.email "41898282+github-actions[bot]@users.noreply.github.com"
           git config --global user.name "github-actions[bot]"
+          git fetch
+          git switch graphics
           git add ${{ steps.figure.outputs.OUTPUT_FILE }}
           git commit -m "benchmark ${{ github.sha }}"
           git config -l | grep 'http\..*\.extraheader' | cut -d= -f1 | \