Firebase Performance metrics disappears on the console after 2 days

[visumickey]

After upgrading to 8.6.0 version of Firebase performance, an issue occurs where the events get lost on the console after a couple of days.

Reason
Firebase Performance received events and processes them at realtime. But the events processed at realtime are available only for 2 days. A separate batch process happens regularly to make sure the events are aggregated regularly. Firebase Performance UI shows data from both realtime processing and batch processing.

Events that were sent on version 8.6.0 (iOS) had an issue where the events were dropped off in the batch processing, but realtime accepts those events. So, the UI would lose data after 2 days since batch processing drops those events off.

This does not affect any SDK versions except for 8.6.0.

[visumickey]

The fix for this issue (#8578) is ready and we are the final stages of testing before rolling out the fix.

The expected new release is 8.6.1 and we HIGHLY recommend to upgrade to this newer version to make sure the events are not lost.

[visumickey]

Fix for this issue has landed with version 8.6.1 for CocoaPods and Swift Package Manager.

### Please upgrade to version 8.6.1 or above to make sure your events are ingested and processed successfully.

Carthage and zip distribution users: Until 8.7.0 releases, please rollback to the 8.5.0 version of FirebasePerformance.