Do not throw errors when trying to list members from a non-existent Google Group

src/dispatch/plugins/dispatch_google/groups/plugin.py

@@ -170,11 +170,16 @@ def remove(self, email: str, participants: List[str]):
         for p in participants:
             remove_member(client, email, p)
 
-    def list(self, email: str):
+    def list(self, email: str) -> list[str]:
         """Lists members from an existing Google Group."""
         client = get_service(self.configuration, "admin", "directory_v1", self.scopes)
-        members = list_members(client, email)
-        return [m["email"] for m in members.get("members", [])]
+        try:
+            members = list_members(client, email)
+            return [m["email"] for m in members.get("members", [])]
+        except HttpError as e:
+            if e.resp.status == 404:
+                log.warning(f"Group does not exist. GroupKey={email} Trying to list members.")
+        return []
 
     def delete(self, email: str):
         """Deletes an existing Google group."""