Bump serialize-javascript and workbox-cli

Bumps [serialize-javascript](https://github.com/yahoo/serialize-javascript) to 6.0.2 and updates ancestor dependency [workbox-cli](https://github.com/googlechrome/workbox). These dependencies need to be updated together.


Updates `serialize-javascript` from 4.0.0 to 6.0.2
- [Release notes](https://github.com/yahoo/serialize-javascript/releases)
- [Commits](yahoo/serialize-javascript@v4.0.0...v6.0.2)

Updates `workbox-cli` from 6.5.4 to 7.3.0
- [Release notes](https://github.com/googlechrome/workbox/releases)
- [Commits](GoogleChrome/workbox@v6.5.4...v7.3.0)

---
updated-dependencies:
- dependency-name: serialize-javascript
  dependency-type: indirect
- dependency-name: workbox-cli
  dependency-type: direct:production
...

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