handle get_data exceptions better

Makes exception handling more precise, only raising status for 401s.

Also fixes a string pylint was complaining about.

bookwyrm/activitypub/base_activity.py

@@ -306,7 +306,8 @@ def resolve_remote_id(
 
 
 def get_representative():
-    """Get or create an actor representing the entire instance to sign requests to 'secure mastodon' servers"""
+    """Get or create an actor representing the instance
+     to sign requests to 'secure mastodon' servers"""
     username = f"{INSTANCE_ACTOR_USERNAME}@{DOMAIN}"
     try:
         user = models.User.objects.get(username=username)

bookwyrm/connectors/abstract_connector.py

@@ -244,7 +244,11 @@ def get_data(url, params=None, timeout=settings.QUERY_TIMEOUT):
         raise ConnectorException(err)
 
     if not resp.ok:
-        resp.raise_for_status()
+        if resp.status_code == 401:
+            # this is probably an AUTHORIZED_FETCH issue
+            resp.raise_for_status()
+        else:
+            raise ConnectorException()
     try:
         data = resp.json()
     except ValueError as err: