Default header-only to None

This behavior is identical but None reads better than sys.maxsize

src/inspect_ai/_view/view.py

@@ -151,7 +151,7 @@ def handle_log(self) -> None:
         # read query parameters from the URL
         query_params = parse_qs(parsed.query)
         header_param = query_params.get("header-only", None)
-        header_only = int(header_param[0]) if header_param is not None else sys.maxsize
+        header_only = int(header_param[0]) if header_param is not None else None
 
         # reconstruct the path
         path = urlunparse(