fix: remove unsupported --hostname/--username from lb config

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

iso/builder/auto/config

@@ -23,8 +23,6 @@ lb config noauto \
     --memtest none \
     --iso-volume "BEE-DEBUG" \
     --iso-application "Bee Hardware Audit" \
-    --hostname "bee-debug" \
-    --username "root" \
     --bootappend-live "boot=live components quiet splash" \
     --apt-recommends false \
     "${@}"