[metric] last_sync_timestamp_seconds is misleading

[gozer]

What would you like to be added:

I would like 2 distinct metrics to track the last sync timestamp of the main reconciliation loop.

The current last_sync_timestamp_seconds that I wish was called last_successful_sync_timestamp_seconds

And one last_reconcile_timestamp_seconds that recorded a new timestamp for the reconcile loop, wether it completed successfully or not.

Why is this needed:

Right now, I can't differentiate between the sync loop lagging because the operator is overworked or some timing issues from an error encountered during a reconciliation pass.

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/lifecycle stale

[gozer]

/remove-lifecycle stale