Revert "config: use the pipewire directory"
This MR reverts back commit 8f541e9e as it does not allow wireplumber to run correctly if installed in the system.
The commit was originally added because we wanted the configuration to be stored in the pipewire subdirectory, but after re-thinking the configuration refactoring, we eventually changed our mind and decided to keep it under the wireplumbver subdirectory, like master.
cc @ashoks