Make it compatible with the Sound Naming spec
Important: This change is meant for KF6/Plasma 6 only, so wait until it's safe to merge.
Make it compatible with the sound naming spec. See https://invent.kde.org/raploz/blue-ocean-sound-theme/-/issues/6
https://specifications.freedesktop.org/sound-naming-spec/sound-naming-spec-latest.html
Some of the sounds are not in the spec but are available in the Oxygen theme.