Infodesk add dial-in number

docs/facilities.md

@@ -9,7 +9,7 @@ Announcements!
 ### How to contact us
 
 * Infodesk Tent: [At O 13](https://map.events.ccc.de/camp/2023/map/#17.48/53.030177/13.305944/G,M,O) at the main way leading straight away from the entrance after 250m.
-* DECT: 1111 (Dial-In-Number: TBD)
+* DECT: 1111 (Dial-In-Number: +49 330 747987 1111)
 * Matrix: [#camp2023-infodesk:events.ccc.de](https://matrix.to/#/#camp2023-infodesk:events.ccc.de)
 * IRC: #c3infodesk on hackint.org
 * Mastodon: [@c3infodesk@chaos.social](https://chaos.social/@c3infodesk) (requests via the other channels are preferred).