.forgejo/workflows/ci.yaml: adaptation to auto cancel

.forgejo/workflows/ci.yaml

@@ -1,20 +1,22 @@
+name: DNS automated deployment
 on:
   push:
     branches:
       - 'main'
 
 jobs:
-  deploy_script:
+  deploy:
     runs-on: linux_amd64
     steps:
       - name: Apply zone changes
         shell: bash
         run: |
+          LAST_RUN=$(cat /home/runner/last_run)
           CURRENT_ZONE=
           echo "Preparing to update ${{ vars.DNS_SERVER }}..."
           git clone ${{ gitea.server_url }}/${{ gitea.repository }} dns
           cd dns
-          git diff HEAD^ HEAD > zone_diff.txt
+          git diff $LAST_RUN ${{ env.GITHUB_SHA }} > zone_diff.txt
           echo "${{ secrets.TSIG_KEY }}" | base64 -d > temp_keyfile
           while IFS= read -r line; do
             case "$line" in
@@ -48,3 +50,4 @@ jobs:
             esac
           done < zone_diff.txt
           rm temp_keyfile
+          echo ${{ env.GITHUB_SHA }} > /home/runner/last_run