Bump superdesk-core from 3dc4662 to 904da8b in /client

Bumps [superdesk-core](https://github.com/superdesk/superdesk-client-core) from `3dc4662` to `904da8b`.
- [Release notes](https://github.com/superdesk/superdesk-client-core/releases)
- [Commits](superdesk/superdesk-client-core@3dc4662...904da8b)

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

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