Update dependency firebase to v8.7.1

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
firebase (source, changelog)	8.6.8 -> 8.7.1

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Release Notes

firebase/firebase-js-sdk

### [`v8.7.1`](https://togithub.com/firebase/firebase-js-sdk/compare/firebase@8.7.0...firebase@8.7.1) [Compare Source](https://togithub.com/firebase/firebase-js-sdk/compare/firebase@8.7.0...firebase@8.7.1) ### [`v8.7.0`](https://togithub.com/firebase/firebase-js-sdk/compare/firebase@8.6.8...firebase@8.7.0) [Compare Source](https://togithub.com/firebase/firebase-js-sdk/compare/firebase@8.6.8...firebase@8.7.0)

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Configuration

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