code: async function removeDir(dirPath) {
    let isExist = await checkDirExist(dirPath)
  
    return new Promise((resolve, reject) => {
      if (!isExist) {
        resolve()
      } else {
        rimraf(dirPath, err => {
          if (err) reject(err)
          else resolve()
        })
      }
    })
  }
docs: 删除目录