nixos/nm-file-secret-agent: add `trim` option

      // lib.optionalAttrs (i.matchSetting != null) {

        match_setting = i.matchSetting;

      }

      // lib.optionalAttrs (i.trim != null) { trim = i.trim; }

    ) cfg.ensureProfiles.secrets.entries;

  };

  nmFileSecretAgentConfigFile = toml.generate "config.toml" nmFileSecretAgentConfig;

                description = "file from which the secret value is read";

                type = lib.types.str;

              };

              trim = lib.mkOption {

                description = "whether leading and trailing whitespace should be stripped from the files content before being passed to NetworkManager";

                type = lib.types.nullOr lib.types.bool;

                default = null;

              };

            };

          }

        );