Distribution check: Remove EOL Ubuntu releases

See also https://ubuntu.com/about/release-cycle

cmake_targets/tools/build_helper

@@ -104,9 +104,7 @@ check_supported_distribution() {
     local distribution=$(get_distribution_release)
     case "$distribution" in
         "ubuntu24.04") return 0 ;;
-        "ubuntu23.10") return 0 ;;
         "ubuntu22.04") return 0 ;;
-        "ubuntu21.04") return 0 ;;
         "ubuntu20.04") return 0 ;;
         "debian11")    return 0 ;;
         "fedora40")    return 0 ;;
@@ -536,7 +534,7 @@ check_install_additional_tools (){
   local optional_packages=""
   if [[ "$OS_BASEDISTRO" == "debian" ]]; then
     case "$(get_distribution_release)" in
-        "ubuntu20.04" | "ubuntu21.04" | "ubuntu22.04" | "debian11" )
+        "ubuntu20.04" | "ubuntu22.04" | "debian11" )
             optional_packages="python3 python3-pip python3-dev python3-scipy python3-matplotlib python3-pyroute2 universal-ctags"
             ;;
     esac