package/less: bump to version 685

Release notes since 661:
https://www.greenwoodsoftware.com/less/news.668.html
https://www.greenwoodsoftware.com/less/news.678.html
https://www.greenwoodsoftware.com/less/news.679.html
https://www.greenwoodsoftware.com/less/news.685.html



Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Julien Olivain <ju.o@free.fr>