Bump newsroom-core from db82d87 to ff2815d in /client

Bumps [newsroom-core](https://github.com/superdesk/newsroom-core) from `db82d87` to `ff2815d`.
- [Release notes](https://github.com/superdesk/newsroom-core/releases)
- [Commits](superdesk/newsroom-core@db82d87...ff2815d)

---
updated-dependencies:
- dependency-name: newsroom-core
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>