build(deps): update boon requirement from 0.5 to 0.6

Updates the requirements on [boon](https://github.com/santhosh-tekuri/boon) to permit the latest version.
- [Release notes](https://github.com/santhosh-tekuri/boon/releases)
- [Changelog](https://github.com/santhosh-tekuri/boon/blob/main/CHANGELOG.md)
- [Commits](santhosh-tekuri/boon@v0.5.0...v0.6.0)

---
updated-dependencies:
- dependency-name: boon
  dependency-type: direct:production
...

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

Author: dependabot[bot]

cdevents-sdk/Cargo.toml

@@ -21,7 +21,7 @@ time = { version = "0.3", features = ["serde-human-readable"] }
 
 [dev-dependencies]
 assert-json-diff = "2.0"
-boon = "0.5"
+boon = "0.6"
 glob = "0.3"
 proptest = "1"
 rstest = "0.18"