amd64 image binding

.woodpecker/notification.yml

@@ -8,6 +8,9 @@ matrix:
       NOTIFICATION_TELEGRAM_SECRET_PATH: sendico/notification/telegram
       NOTIFICATION_ENV: prod
 
+labels:
+  platform: linux/amd64
+
 when:
   - event: push
     branch: main
@@ -85,6 +88,7 @@ steps:
     image: gcr.io/kaniko-project/executor:debug
     depends_on: [ backend-lint, backend-tests, secrets ]
     commands:
+      - '[ "$(uname -m)" = "x86_64" ] || { echo "image build requires an amd64 runner"; exit 1; }'
       - sh ci/scripts/notification/build-image.sh
 
   - name: deploy