Bump plek from 5.1.0 to 5.2.0

Bumps [plek](https://github.com/alphagov/plek) from 5.1.0 to 5.2.0.
- [Changelog](https://github.com/alphagov/plek/blob/main/CHANGELOG.md)
- [Commits](alphagov/plek@v5.1.0...v5.2.0)

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

Signed-off-by: dependabot[bot] <support@github.com>

Gemfile.lock

@@ -482,7 +482,7 @@ GEM
       ast (~> 2.4.1)
       racc
     pg (1.5.6)
-    plek (5.1.0)
+    plek (5.2.0)
     prometheus_exporter (2.1.0)
       webrick
     pry (0.14.2)