[DEV/DEP]: Bump puppeteer from 20.7.4 to 21.2.1

Bumps [puppeteer](https://github.com/puppeteer/puppeteer) from 20.7.4 to 21.2.1.
- [Release notes](https://github.com/puppeteer/puppeteer/releases)
- [Changelog](https://github.com/puppeteer/puppeteer/blob/main/release-please-config.json)
- [Commits](puppeteer/puppeteer@puppeteer-v20.7.4...puppeteer-v21.2.1)

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

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

package.json

@@ -36,7 +36,7 @@
         "lru-cache": "^10.0.0",
         "mocha": "~10.2.0",
         "nyc": "^15.1.0",
-        "puppeteer": "~20.7.2",
+        "puppeteer": "~21.2.1",
         "terser": "~5.18.1",
         "vue-tabs-component": "^1.5.0",
         "vuepress": "^1.9.7",