Update navigation.yml

Author: spetruzza

_data/navigation.yml

@@ -140,7 +140,7 @@ menu:
                 - text: "Organize a meetup"
                   description: "Meet people for discussion and shared experiences"
                   url: "/year/2021/info/call-participation/meetups"
-                - text: "Become a student volunteer (coming soon)"
+                - text: "Become a student volunteer"
                   description: "Support the conference and build your research network"
                   url: "http://www.vissv.org"
                   is_external: true