Bump parallel_tests from 4.5.2 to 4.6.0

Bumps [parallel_tests](https://github.com/grosser/parallel_tests) from 4.5.2 to 4.6.0.
- [Changelog](https://github.com/grosser/parallel_tests/blob/master/CHANGELOG.md)
- [Commits](grosser/parallel_tests@v4.5.2...v4.6.0)

---
updated-dependencies:
- dependency-name: parallel_tests
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

Gemfile.lock

@@ -57,7 +57,7 @@ GEM
     mini_mime (1.1.5)
     multi_test (1.1.0)
     parallel (1.24.0)
-    parallel_tests (4.5.2)
+    parallel_tests (4.6.0)
       parallel
     parser (3.3.0.5)
       ast (~> 2.4.1)