Bump ejs and workbox-webpack-plugin in /packages/utility-scripts

Bumps [ejs](https://github.com/mde/ejs) to 3.1.10 and updates ancestor dependency [workbox-webpack-plugin](https://github.com/googlechrome/workbox). These dependencies need to be updated together.


Updates `ejs` from 2.7.4 to 3.1.10
- [Release notes](https://github.com/mde/ejs/releases)
- [Commits](mde/ejs@v2.7.4...v3.1.10)

Updates `workbox-webpack-plugin` from 6.3.0 to 6.6.0
- [Release notes](https://github.com/googlechrome/workbox/releases)
- [Commits](GoogleChrome/workbox@v6.3.0...v6.6.0)

---
updated-dependencies:
- dependency-name: ejs
  dependency-type: indirect
- dependency-name: workbox-webpack-plugin
  dependency-type: direct:production
...

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Author: dependabot[bot]