fix Cannot fetch local actor webfinger

Part-of: <https://dev.funkwhale.audio/funkwhale/funkwhale/-/merge_requests/2861>

api/funkwhale_api/federation/authentication.py

@@ -81,6 +81,7 @@ class SignatureAuthentication(authentication.BaseAuthentication):
         fetch_delay = 24 * 3600
         now = timezone.now()
         last_fetch = actor.domain.nodeinfo_fetch_date
+        if not actor.domain.is_local:
             if not last_fetch or (
                 last_fetch < (now - datetime.timedelta(seconds=fetch_delay))
             ):