chore(deps-dev): bump puppeteer from 19.9.1 to 20.8.1

Bumps [puppeteer](https://github.com/puppeteer/puppeteer) from 19.9.1 to 20.8.1.
- [Release notes](https://github.com/puppeteer/puppeteer/releases)
- [Changelog](https://github.com/puppeteer/puppeteer/blob/main/release-please-config.json)
- [Commits](puppeteer/puppeteer@puppeteer-v19.9.1...puppeteer-v20.8.1)

---
updated-dependencies:
- dependency-name: puppeteer
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>