editors/quilter: unbreak build after d0c0d264eeb5
meson.build:87:4: ERROR: Dependency "gtksourceview-4" not found, tried pkgconfig
Error: Missing: share/glib-2.0/schemas/io.github.lainsce.Quilter.gschema.xml
Note, GLIB_SCHEMAS pointlessly complicates pkg-plist after 522332dbc718.
PR: 282033
Reported by: pkg-fallout