[Cargo]: bump serial_test from 3.3.1 to 3.4.0 (#138)

Bumps [serial_test](https://github.com/palfrey/serial_test) from 3.3.1 to 3.4.0.
- [Release notes](https://github.com/palfrey/serial_test/releases)
- [Commits](palfrey/serial_test@v3.3.1...v3.4.0)

---
updated-dependencies:
- dependency-name: serial_test
  dependency-version: 3.4.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Cargo.lock

@@ -59,7 +59,7 @@ mockall = "0.14.0"
 assert_matches = "1.5.0"
 tempfile = "3.25.0"
 tower = { version = "0.5.3", features = ["util"] }
-serial_test = "3.3.1"
+serial_test = "3.4.0"
 
 # local testing: ignore
 #git = "https://github.com/kube-rs/kube.git"