Bump rxjs from 6.4.0 to 6.5.1
Bump rxjs from 6.4.0 to 6.5.1

Bumps [rxjs](https://github.com/reactivex/rxjs) from 6.4.0 to 6.5.1.
- [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/6.4.0...6.5.1)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
sue445/chrome-gitlab-notifier,sue445/chrome-gitlab-notifier