trivial: Fix the Since: value on as_utils_is_spdx_license()
trivial: Fix the Since: value on as_utils_is_spdx_license()

ximion/appstream-glib,hughsie/appstream-glib,hughsie/appstream-glib,hughsie/appstream-glib,ikeydoherty/appstream-glib,ximion/appstream-glib,ximion/appstream-glib,ikeydoherty/appstream-glib