Bump serialize-javascript from 6.0.2 to 7.0.4 in /client_js

Bumps [serialize-javascript](https://github.com/yahoo/serialize-javascript) from 6.0.2 to 7.0.4.
- [Release notes](https://github.com/yahoo/serialize-javascript/releases)
- [Commits](yahoo/serialize-javascript@v6.0.2...v7.0.4)

---
updated-dependencies:
- dependency-name: serialize-javascript
  dependency-version: 7.0.4
  dependency-type: indirect
...

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Author: dependabot[bot]