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

Bumps [@backstage/plugin-catalog-backend](https://github.com/backstage/backstage/tree/HEAD/plugins/catalog-backend) from 1.24.0 to 1.26.0.
- [Release notes](https://github.com/backstage/backstage/releases)
- [Changelog](https://github.com/backstage/backstage/blob/master/plugins/catalog-backend/CHANGELOG.md)
- [Commits](https://github.com/backstage/backstage/commits/v1.26.0/plugins/catalog-backend)

---
updated-dependencies:
- dependency-name: "@backstage/plugin-catalog-backend"
  dependency-type: direct:production
...

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