this change is a follow up of ca7f7bf8e2, which changed the output path to build/$<CONFIG>/debian. but what dist/docker/debian/build_docker.sh expects is `build/dist/$config/debian/*.deb`, where `$config` is the normalized mode, when the debian packages are built using CMake generated rules, `$mode` is CMake configuration name, i.e., `$<CONFIG>`. so, ca7f7bf8e2 made a mistake, as it does not match the expectation of `build_docker.sh`.
in this change, this issue is addressed. so we use the same path in both `dist/CMakeLists.txt` and `dist/docker/debian/build_docker.sh`.
Closesscylladb/scylladb#17848
* github.com:scylladb/scylladb:
build: cmake: add dist-* targets to the default build target
build: cmake: put server deb packages under build/dist/$<CONFIG>/debian