[docs] Updated FUNDING.yml

[skip ci]

Author: nemesifier

.github/FUNDING.yml

@@ -1,5 +1,5 @@
 # These are supported funding model platforms
-github: # Replace with up to 4 GitHub Sponsors-enabled usernames e.g., [user1, user2]
+github: [openwisp]
 patreon: # Replace with a single Patreon username
 open_collective: # Replace with a single Open Collective username
 ko_fi: # Replace with a single Ko-fi username