Update dependency rxjs to v7.8.1

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
rxjs (source)	7.8.0 -> 7.8.1

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Release Notes

reactivex/rxjs

### [`v7.8.1`](https://togithub.com/reactivex/rxjs/compare/7.8.0...7.8.1) [Compare Source](https://togithub.com/reactivex/rxjs/compare/7.8.0...7.8.1)

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Configuration

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