build: add docker trigger for release builds

circle.yml

@@ -53,4 +53,5 @@ deployment:
       - go run build.go sha1-dist
       - aws s3 sync ./dist s3://$BUCKET_NAME/release
       - ./scripts/trigger_windows_build.sh ${APPVEYOR_TOKEN} ${CIRCLE_SHA1} release
+      - ./scripts/trigger_docker_build.sh ${TRIGGER_GRAFANA_PACKER_CIRCLECI_TOKEN} ${CIRCLE_TAG}