Remove Jabber communication channel

While it would be nice to be able to use Jabber, it is effectively not happening.
There are a few people hanging out in the lounge, but the community is not meeting
there and it does not make sense to announce it as a channel.

src/SpaceApiEntry.py

@@ -13,7 +13,6 @@ def create_netz39():
         )
         entry.add_contact("email", "[email protected]", is_issue_channel=True)
         entry.add_contact("ml", "[email protected]", is_issue_channel=True)
-        entry.add_contact("jabber", "[email protected]")
         entry.add_contact("discord", "https://discord.netz39.de/")
         entry.add_contact("github", "https://github.com/Netz39")
         entry.add_contact("mastodon", "https://machteburch.social/@netz39")