rebuildSlugsForSlugChange fails when changing slug of a localized root page
Changing a slug of a site with L>0 and pid=0 throws a
SiteNotFoundException on save.
rebuildSlugsForSlugChange calls SiteFinder::getSiteByPageId() with the pageId of the localized page. This page however has pid=0 set.
Therefore, it's not possible find any site configuration, because they are always mapped to the uid of the default page which we can not determine in this case.
: Change the slug field of a localized root page in the page properties and try to save the page record.