When creating presets in some panels, names like "Default" can be used
which are the same preset names as bundled presets. New entries created
like this can't be deleted because blender will treat it as a bundled
preset which then leaves stale entries in the list. This fix prevents
those kind of preset names to be used during creation.
Pull Request: https://projects.blender.org/blender/blender/pulls/142652
f74ad86748