chore(deps-dev): bump rake in /fluent-plugin-enhance-k8s-metadata

Bumps [rake](https://github.com/ruby/rake) from 13.2.0 to 13.2.1.
- [Release notes](https://github.com/ruby/rake/releases)
- [Changelog](https://github.com/ruby/rake/blob/master/History.rdoc)
- [Commits](ruby/rake@v13.2.0...v13.2.1)

---
updated-dependencies:
- dependency-name: rake
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

fluent-plugin-enhance-k8s-metadata/Gemfile.lock

@@ -92,7 +92,7 @@ GEM
       connection_pool (~> 2.2)
     power_assert (2.0.3)
     public_suffix (5.0.4)
-    rake (13.2.0)
+    rake (13.2.1)
     recursive-open-struct (1.1.3)
     rexml (3.2.6)
     ruby2_keywords (0.0.5)