fix(webdav): Increase max upload size

- Fixes issue with Zotero sync

modules/nixos/deertopia/webdav.nix

@@ -98,6 +98,9 @@ in {
           # See previous note regarding the HTTPS -> HTTP redirection.
           proxy_set_header Destination $http_destination_webdav;
 
+          # Increase limit of upload sizes.
+          client_max_body_size 20G;
+
           proxy_pass "http://localhost:${builtins.toString cfg.port}";
         '';
       };