chore(example/deps): update dependency cloud_firestore to v6.4.1

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
cloud_firestore (source)	dependencies	minor	6.3.0 → 6.4.1

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Release Notes

firebase/flutterfire (cloud_firestore)

v6.4.1

Compare Source

• Update a dependency to the latest release.

v6.4.0

Compare Source

• REFACTOR: move all packages to workspace (#​18182). (6cdfcb10)
• FIX(firestore,web): update Timestamp handling in jsify and EncodeUtility (#​18264). (9783a448)
• FIX(firestore,windows): fix CI issue (#​18218). (b9c8a9e2)
• FEAT: upgrade pigeon to version 26.3.4 (#​18205). (cb6b4aef)

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⚠️ Artifact update problem

Renovate failed to update an artifact related to this branch. You probably do not want to merge this PR as-is.

♻ Renovate will retry this branch, including artifacts, only when one of the following happens:

• any of the package files in this branch needs updating, or
• the branch becomes conflicted, or
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The artifact failure details are included below:

File name: example/pubspec.lock

Command failed: flutter pub upgrade cloud_firestore
Because firebase_core 4.7.0 depends on firebase_core_platform_interface ^6.0.3 and cloud_firestore >=6.4.1 depends on firebase_core_platform_interface ^7.0.1, firebase_core 4.7.0 is incompatible with cloud_firestore >=6.4.1.
So, because firestore_cache_example depends on both cloud_firestore 6.4.1 and firebase_core 4.7.0, version solving failed.


You can try one of the following suggestions to make the pubspec resolve:
* Try upgrading your constraint on firebase_core: flutter pub add firebase_core:^4.9.0
* Consider downgrading your constraint on cloud_firestore: flutter pub add cloud_firestore:^6.3.0
Failed to update packages.