chore(deps): bump mvdan.cc/sh/v3 from 3.8.0 to 3.9.0 in /plugins/cron

Bumps [mvdan.cc/sh/v3](https://github.com/mvdan/sh) from 3.8.0 to 3.9.0.
- [Release notes](https://github.com/mvdan/sh/releases)
- [Changelog](https://github.com/mvdan/sh/blob/master/CHANGELOG.md)
- [Commits](https://github.com/mvdan/sh/compare/v3.8.0...v3.9.0)

---
updated-dependencies:
- dependency-name: mvdan.cc/sh/v3
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

plugins/cron/go.mod

@@ -9,7 +9,7 @@ require (
 	github.com/robfig/cron/v3 v3.0.1
 	github.com/ryanuber/columnize v2.1.2+incompatible
 	github.com/spf13/pflag v1.0.5
-	mvdan.cc/sh/v3 v3.8.0
+	mvdan.cc/sh/v3 v3.9.0
 )
 
 require (