async _readPackageJson() {
    const packageJsonPath = path.join(
      this.serverless.serviceDir,
      'package.json',
    )

    if (existsSync(packageJsonPath)) {
      const packageJsonStr = await readFile(packageJsonPath, 'utf-8')
      return JSON.parse(packageJsonStr)
    }

    return {}
  }
Reads the package.json file in the service directory.
Note: This is a memoized function up in the constructor.

@returns {Object} - The package.json object