build(deps): update colored_json requirement from 2.1.0 to 3.0.1

Updates the requirements on [colored_json](https://github.com/ctron/colored_json) to permit the latest version.
- [Release notes](https://github.com/ctron/colored_json/releases)
- [Commits](https://github.com/ctron/colored_json/commits)

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

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

varlink-cli/Cargo.toml

@@ -21,7 +21,7 @@ varlink_parser = { version = "4.2", path = "../varlink_parser" }
 serde = "1.0.102"
 serde_json = "1.0.41"
 clap = "2.33.0"
-colored_json = "2.1.0"
+colored_json = "3.0.1"
 chainerror = "0.7.0"
 libc = { version = "0.2.126", default-features = false }
 bitflags = "1.2.1"