Bump @backstage/plugin-catalog-backend-module-ldap in /backstage

Bumps [@backstage/plugin-catalog-backend-module-ldap](https://github.com/backstage/backstage/tree/HEAD/plugins/catalog-backend-module-ldap) from 0.5.20 to 0.5.21.
- [Release notes](https://github.com/backstage/backstage/releases)
- [Changelog](https://github.com/backstage/backstage/blob/master/plugins/catalog-backend-module-ldap/CHANGELOG.md)
- [Commits](https://github.com/backstage/backstage/commits/HEAD/plugins/catalog-backend-module-ldap)

---
updated-dependencies:
- dependency-name: "@backstage/plugin-catalog-backend-module-ldap"
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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