Inconsistency between commands from README file and what actually works

I guess this is a bug, not a problem with the README file

README:

./defs2bst/defs2bst.py --ybd ybd/ybd.py \
                       --definitions definitions \
                       --output buildstream-tests/elements \
                       --rebase strata/build-essential.morph gnu-toolchain.bst \
                       gnome/systems/gnome-system-x86_64.morph x86_64

What it works:

./defs2bst/defs2bst.py --ybd ybd/ybd.py \
                       --definitions definitions \
                       --output buildstream-tests \
                       --rebase strata/build-essential.morph gnu-toolchain.bst \
                       gnome/systems/gnome-system-x86_64.morph x86_64

(The only difference is --output buildstream-tests)