Metric cortex_ingester_chunks_stored_total ignores chunk write deduping

[bboreham]

Metric cortex_ingester_chunks_stored_total, which counts chunks stored per user, is incremented for every chunk sent to the store, regardless of whether it was already stored by another ingester and hence skipped.

This means we are not getting a true readout of the impact of each user on resource utilisation.

Similarly cortex_ingester_chunk_stored_bytes_total

[stale]

This issue has been automatically marked as stale because it has not had any activity in the past 30 days. It will be closed in 7 days if no further activity occurs. Thank you for your contributions.

[pstibrany]

Fixed by #2463.