Bump ejs and workbox-build

Bumps [ejs](https://github.com/mde/ejs) and [workbox-build](https://github.com/googlechrome/workbox). These dependencies needed to be updated together.

Updates `ejs` from 2.7.4 to 3.1.8
- [Release notes](https://github.com/mde/ejs/releases)
- [Changelog](https://github.com/mde/ejs/blob/main/CHANGELOG.md)
- [Commits](mde/ejs@v2.7.4...v3.1.8)

Updates `workbox-build` from 6.1.5 to 6.5.4
- [Release notes](https://github.com/googlechrome/workbox/releases)
- [Commits](GoogleChrome/workbox@v6.1.5...v6.5.4)

---
updated-dependencies:
- dependency-name: ejs
  dependency-type: indirect
- dependency-name: workbox-build
  dependency-type: indirect
...

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Author: dependabot[bot]