build(deps): Bump the rust group in /functional-tests with 2 updates

Bumps the rust group in /functional-tests with 2 updates: [serde](https://github.com/serde-rs/serde) and [serde_derive](https://github.com/serde-rs/serde).


Updates `serde` from 1.0.223 to 1.0.226
- [Release notes](https://github.com/serde-rs/serde/releases)
- [Commits](serde-rs/serde@v1.0.223...v1.0.226)

Updates `serde_derive` from 1.0.223 to 1.0.226
- [Release notes](https://github.com/serde-rs/serde/releases)
- [Commits](serde-rs/serde@v1.0.223...v1.0.226)

---
updated-dependencies:
- dependency-name: serde
  dependency-version: 1.0.226
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: rust
- dependency-name: serde_derive
  dependency-version: 1.0.226
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: rust
...

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Author: dependabot[bot]