How to use the just-scripts-utils.exec function in just-scripts-utils

const args = Object.keys(options).reduce(
        (args, option) => {
          if (typeof options[option] === 'string') {
            return args.concat(['--' + option, options[option] as string]);
          } else if (typeof options[option] === 'boolean') {
            return args.concat(['--' + option]);
          }

          return args;
        },
        [tscCmd]
      );

      const cmd = encodeArgs([process.execPath, ...args]).join(' ');
      logger.info(`Executing: ${cmd}`);
      return exec(cmd);
    } else {
      Promise.resolve();
    }
  };
}

const args = [
        '--project',
        projectFile,
        '-t',
        'stylish',
        '-r',
        path.dirname(resolve('tslint-microsoft-contrib') || '')
      ];

      if (options.fix) {
        args.push('--fix');
      }

      const cmd = encodeArgs([process.execPath, tslintCmd, ...args]).join(' ');
      logger.info(cmd);
      return exec(cmd, { stdout: process.stdout, stderr: process.stderr });
    } else {
      return Promise.resolve();
    }
  };
}