Bump rxjs from 7.5.5 to 7.5.6 in /src-ui

Bump rxjs from 7.5.5 to 7.5.6 in /src-ui

Bumps [rxjs](https://github.com/reactivex/rxjs) from 7.5.5 to 7.5.6.
- [Release notes](https://github.com/reactivex/rxjs/releases)
- [Changelog](https://github.com/ReactiveX/rxjs/blob/master/CHANGELOG.md)
- [Commits](https://github.com/reactivex/rxjs/compare/7.5.5...7.5.6)

---
updated-dependencies:
- dependency-name: rxjs
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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