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

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


Updates `tempfile` from 3.15.0 to 3.16.0
- [Changelog](https://github.com/Stebalien/tempfile/blob/master/CHANGELOG.md)
- [Commits](Stebalien/tempfile@v3.15.0...v3.16.0)

Updates `serde_json` from 1.0.137 to 1.0.138
- [Release notes](https://github.com/serde-rs/json/releases)
- [Commits](serde-rs/json@v1.0.137...v1.0.138)

---
updated-dependencies:
- dependency-name: tempfile
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: rust
- dependency-name: serde_json
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: rust
...

Signed-off-by: dependabot[bot] <[email protected]>

functional-tests/Cargo.toml

@@ -5,9 +5,9 @@ edition = "2021"
 authors = ["Adrian Utrilla <[email protected]>"]
 
 [dependencies]
-tempfile = "3.15.0"
+tempfile = "3.16.0"
 serde = "1.0"
-serde_json = "1.0.137"
+serde_json = "1.0.138"
 serde_yaml = "0.9.34"
 serde_derive = "1.0"
 lazy_static = "1.5.0"