Merge branch 'update-2021-06-11' into 'master'

Update Registration Link and Tutors for 2021-06-11-git-and-gitlab.md

See merge request hifis/hifis.net!240

_events/2021/06/2021-06-11-git-and-gitlab.md

@@ -4,13 +4,14 @@ layout: event
 organizers:
   - erxleben
 lecturers:
-  - TBA
+  - Helene Hoffmann
+  - Lokamani
 type:   workshop
 start:
     date:   "2021-06-11"
 end:
     date:   "2021-06-14"
-registration_link:
+registration_link: "https://events.hifis.net/event/123/"
 location:
     campus: Online
 fully_booked_out: false