Use unique WORKDIR per run via github.run_id

.forgejo/workflows/deploy.yml

@@ -13,25 +13,26 @@ jobs:
     steps:
       - name: Clone repo
         run: |
-          rm -rf /tmp/brand-site
-          git clone http://localhost:3000/sscoble/brand-site.git /tmp/brand-site
-          cd /tmp/brand-site
+          export WORKDIR=/tmp/brand-site-${{ github.run_id }}
+          git clone http://localhost:3000/sscoble/brand-site.git "$WORKDIR"
+          cd "$WORKDIR"
           git checkout ${{ github.sha }}
+          echo "WORKDIR=$WORKDIR" >> $GITHUB_ENV
 
       - name: Build website with Nix
-        working-directory: /tmp/brand-site
         run: nix build .#website --no-write-lock-file
+        working-directory: ${{ env.WORKDIR }}
 
       - name: Build speaker profile PDF
-        working-directory: /tmp/brand-site
         run: nix build .#speaker-profile --no-write-lock-file
+        working-directory: ${{ env.WORKDIR }}
 
       - name: Copy build artifacts
         run: |
           mkdir -p ./dist
-          cp -r /tmp/brand-site/result/* ./dist/
+          cp -r ${{ env.WORKDIR }}/result/* ./dist/
           mkdir -p ./public/downloads
-          cp /tmp/brand-site/result-2/* ./public/downloads/ 2>/dev/null || true
+          cp ${{ env.WORKDIR }}/result-2/* ./public/downloads/ 2>/dev/null || true
 
       - name: Configure rclone
         run: |