templates.flights.list: add missing slash to show link
templates.flights.list: add missing slash to show link

The real problem is that URIs should be valid with and without
trailing slash...

dkm/skylines,TobiasLohner/SkyLines,TobiasLohner/SkyLines,snip/skylines,TobiasLohner/SkyLines,skylines-project/skylines,dkm/skylines,Turbo87/skylines,Turbo87/skylines,shadowoneau/skylines,Harry-R/skylines,RBE-Avionik/skylines,dkm/skylines,kerel-fs/skylines,RBE-Avionik/skylines,Harry-R/skylines,kerel-fs/skylines,shadowoneau/skylines,skylines-project/skylines,snip/skylines,shadowoneau/skylines,RBE-Avionik/skylines,shadowoneau/skylines,Harry-R/skylines,RBE-Avionik/skylines,Harry-R/skylines,Turbo87/skylines,skylines-project/skylines,snip/skylines,kerel-fs/skylines,Turbo87/skylines,dkm/skylines,skylines-project/skylines