Update serial_test requirement from 2.0.0 to 3.0.0

Updates the requirements on [serial_test](https://github.com/palfrey/serial_test) to permit the latest version.
- [Release notes](https://github.com/palfrey/serial_test/releases)
- [Commits](palfrey/serial_test@v2.0.0...v3.0.0)

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

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

Cargo.toml

@@ -16,7 +16,7 @@ async-trait = "0.1"
 
 [dev-dependencies]
 mockall = { version = "0.12", default-features = false }
-serial_test = { version = "2.0.0", default-features = false }
+serial_test = { version = "3.0.0", default-features = false }
 criterion = "0.5"
 serde_json = "1"
 rand = "0.8.5"