Bump serialize-javascript and workbox-build in /Build

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

Updates `serialize-javascript` from 6.0.2 to 7.0.5
- [Release notes](https://github.com/yahoo/serialize-javascript/releases)
- [Commits](yahoo/serialize-javascript@v6.0.2...v7.0.5)

Updates `workbox-build` from 7.3.0 to 7.4.1
- [Release notes](https://github.com/googlechrome/workbox/releases)
- [Commits](GoogleChrome/workbox@v7.3.0...v7.4.1)

---
updated-dependencies:
- dependency-name: serialize-javascript
  dependency-version: 7.0.5
  dependency-type: indirect
- dependency-name: workbox-build
  dependency-version: 7.4.1
  dependency-type: indirect
...

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Author: dependabot[bot]