Merge individual Discord server pages with the index page

[TicClick]

[12:17 PM] Walavouchey: they require more maintenance, and beyond a single explanatory paragraph everything else seems like unnecessary info that you can find in the server anyway
[12:18 PM] Walavouchey: the original idea posed in the issue was to list the channels, but none of the current articles do
[12:20 PM] Walavouchey: the modding and mapping hub articles use banners instead of server icons, so if the resolution is an issue they can fit into the first column of a table
[12:27 PM] Walavouchey: could also take the first section of each individual article and make them into subheadings of the index page
--- snip ---
[9:26 PM] RockRoller: sounds good to me?
[9:26 PM] RockRoller: always was of the opinion taht the current form of discord articles is dumb
[9:27 PM] RockRoller: a table is more than enough to list logo + name + owner + other links + short explanation

via

index page is https://osu.ppy.sh/wiki/en/Community/Discord_servers

next steps: #6904