Bump @backstage/backend-app-api from 0.5.8 to 0.5.10

Bumps [@backstage/backend-app-api](https://github.com/backstage/backstage/tree/HEAD/packages/backend-app-api) from 0.5.8 to 0.5.10.
- [Release notes](https://github.com/backstage/backstage/releases)
- [Changelog](https://github.com/backstage/backstage/blob/master/packages/backend-app-api/CHANGELOG.md)
- [Commits](https://github.com/backstage/backstage/commits/HEAD/packages/backend-app-api)

---
updated-dependencies:
- dependency-name: "@backstage/backend-app-api"
  dependency-type: indirect
...

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