Bump debhelper compatibility level to 9: Needed for multiarch-compatible debug files. Tighten build-dependency on debhelper.
Bump debhelper compatibility level to 9: Needed for multiarch-compatible debug files. Tighten build-dependency on debhelper.

tchx84/debian-pkg-sugar-toolkit-gtk3,tchx84/debian-pkg-sugar-toolkit-gtk3,tchx84/debian-pkg-sugar-toolkit-gtk3