Correct name for install_path_scheme in defaults config.yaml (#9482)
Correct name for install_path_scheme in defaults config.yaml (#9482)

Default config.yaml mis-named `install_path_scheme` as `directory_layout`.
This commit corrects the error.
iulian787/spack,iulian787/spack,LLNL/spack,LLNL/spack,LLNL/spack,LLNL/spack,iulian787/spack,iulian787/spack,iulian787/spack,LLNL/spack