dist/docker/debian/build_docker.sh: Build container based on Ubuntu24.04

Now that we added support for Ubuntu24.04 and also migrating our images
to be based on that
(scylladb/scylla-machine-image#530), we should
also modify our docker image

Fixes: scylladb#19738

dist/docker/debian/build_docker.sh

@@ -61,7 +61,7 @@ if [ -f build/build.ninja ]; then
    esac
 fi
 
-container="$(buildah from docker.io/ubuntu:22.04)"
+container="$(buildah from docker.io/ubuntu:24.04)"
 
 packages=(
     "build/dist/$config/debian/${product}_$version-$release-1_$arch.deb"