Add some missing optional route segments to legacy comment route
Add some missing optional route segments to legacy comment route

This was causing tons of broken link warnings to show up in Sentry on
older content.

Discordius/Telescope,Discordius/Telescope,Discordius/Telescope,Discordius/Lesswrong2,Discordius/Telescope,Discordius/Lesswrong2,Discordius/Lesswrong2,Discordius/Lesswrong2