chore(example/deps): update dependency firebase_core to v4.9.0

[renovate]

This PR contains the following updates:

Package	Type	Update	Change	Pending
firebase_core (source)	dependencies	minor	4.7.0 → 4.9.0	4.10.0

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Release Notes

firebase/flutterfire (firebase_core)

v4.9.0

Compare Source

• FIX(core,iOS): use namespaced iOS Pigeon header import (#​18281). (7c1257e7)
• FEAT: bump Firebase iOS SDK to 12.13.0 (#​18273). (78e10f02)
• FEAT: bump Firebase android SDK to 34.13.0 (#​18272). (d10e0ffa)

v4.8.0

Compare Source

• REFACTOR: move all packages to workspace (#​18182). (6cdfcb10)
• FIX: update core, auth and app-check logic so internal resources on method channels are properly disposed (#​18268). (a0de4ed8)
• FEAT(core): Add Auth and AppCheck as App's registered service. (#​18237). (7ce191cb)
• 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
• you click the rebase/retry checkbox if found above, or
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The artifact failure details are included below:

File name: example/pubspec.lock

Command failed: flutter pub upgrade firebase_core
Because firebase_core >=4.9.0 depends on firebase_core_platform_interface ^7.0.1 and cloud_firestore 6.3.0 depends on firebase_core_platform_interface ^6.0.3, firebase_core >=4.9.0 is incompatible with cloud_firestore 6.3.0.
So, because firestore_cache_example depends on both cloud_firestore 6.3.0 and firebase_core 4.9.0, version solving failed.


You can try one of the following suggestions to make the pubspec resolve:
* Try upgrading your constraint on cloud_firestore: flutter pub add cloud_firestore:^6.4.1
* Consider downgrading your constraint on firebase_core: flutter pub add firebase_core:^4.7.0
Failed to update packages.