ci: specify STOPSIGNAL in dockerfile

Signed-off-by: Henry Gressmann <mail@henrygressmann.de>

Author: explodingcamera

scripts/Dockerfile

@@ -1,4 +1,4 @@
-FROM debian:12-slim AS downloader
+FROM debian:13-slim AS downloader
 ARG TAR_URL_AMD64
 ARG TAR_URL_ARM64
 ARG TARGETPLATFORM
@@ -18,4 +18,5 @@ ENV LIWAN_DATA_DIR=/data
 
 COPY --from=downloader /app/liwan /liwan
 ENTRYPOINT ["/liwan"]
-EXPOSE 9042
+EXPOSE 9042
+STOPSIGNAL SIGINT