nixos/gitea: loosen SENDMAIL_PATH type (#421230)

                };

                SENDMAIL_PATH = lib.mkOption {

                  type = lib.types.path;

                  type = lib.types.str;

                  # somewhat duplicated with useSendmail but cannot be deduped because of infinite recursion

                  default =

                    if config.mailer.ENABLED && config.mailer.PROTOCOL == "sendmail" then