Switch to using webhook_bridge instead of lighthouse to trigger the CI.

docker/server/Dockerfile

@@ -4,7 +4,7 @@ COPY . /source
 RUN ls /source/
 RUN natter build --config /source/natter.toml
 
-FROM alpine:3.19 AS server
+FROM alpine:3.20 AS server
 
 RUN apk add --no-cache bash nginx
 RUN addgroup web && adduser -D -G web web && install -d -D -o web -g web -m 700 /srv/http/public