fix(deps): update dependency @google-cloud/firestore to v7

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
@google-cloud/firestore	^6.8.0 -> ^7.1.0

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Release Notes

googleapis/nodejs-firestore (@​google-cloud/firestore)

### [`v7.1.0`](https://togithub.com/googleapis/nodejs-firestore/blob/HEAD/CHANGELOG.md#710-2023-10-11) [Compare Source](https://togithub.com/googleapis/nodejs-firestore/compare/v7.0.0...v7.1.0) ##### Features - Sum and Average aggregations ([#​1873](https://togithub.com/googleapis/nodejs-firestore/issues/1873)) ([b9ea514](https://togithub.com/googleapis/nodejs-firestore/commit/b9ea5143f997dd217200ffa83ed481ad74f558e4)) ### [`v7.0.0`](https://togithub.com/googleapis/nodejs-firestore/blob/HEAD/CHANGELOG.md#700-2023-10-03) [Compare Source](https://togithub.com/googleapis/nodejs-firestore/compare/v6.8.0...v7.0.0) ##### ⚠ BREAKING CHANGES - upgrade to Node 14 ([#​1900](https://togithub.com/googleapis/nodejs-firestore/issues/1900)) - Fix the UpdateData incorrect parameter type issue ([#​1887](https://togithub.com/googleapis/nodejs-firestore/issues/1887)) ##### Features - Fix the UpdateData incorrect parameter type issue ([#​1887](https://togithub.com/googleapis/nodejs-firestore/issues/1887)) ([0afadef](https://togithub.com/googleapis/nodejs-firestore/commit/0afadeff4706e7bff173d8eda7b9681498b570a8)) ##### Bug Fixes - Remove DocumentReference from cursor ([#​1882](https://togithub.com/googleapis/nodejs-firestore/issues/1882)) ([da4f8f8](https://togithub.com/googleapis/nodejs-firestore/commit/da4f8f8b6a35fa93aca0eddc96703d3321a998f6)) ##### Miscellaneous Chores - Upgrade to Node 14 ([#​1900](https://togithub.com/googleapis/nodejs-firestore/issues/1900)) ([1f5abb8](https://togithub.com/googleapis/nodejs-firestore/commit/1f5abb8fbef91e372313b2dbf4d51c7d03ce69b0))

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