docs: use fedi room, remove incomplete listing

docs/intro/contact.md

@@ -12,14 +12,6 @@ title: Get in touch
 
 Here is a link to the [Matrix space](https://matrix.to/#/!xSMwGbdVehScXcIFwS:autonomic.zone?via=autonomic.zone&via=matrix.org&via=1312.media) to see all channels.
 
-- [`#coopcloud:autonomic.zone`](https://matrix.to/#/!JSVYWCRXSVMrAzgeKB:autonomic.zone?via=autonomic.zone) General chat and announcements (low traffic)
-- [`#coopcloud-tech:autonomic.zone`](https://matrix.to/#/!DfXPgKLoYCvjHithgS:autonomic.zone?via=autonomic.zone) Technical discussions (some techno babble)
-- [`#coopcloud-dev:autonomic.zone`](https://matrix.to/#/!IFazIpLtxiScqbHqoa:autonomic.zone?via=autonomic.zone) Intense developer chat (a lot of techno babble)
-
-### XMPP
-
-> Coming Soon :tm:
-
 ## Forum
 
 [`community.coops.tech`](https://community.coops.tech/)