storage: reinstate snapshot status reporting

[jordanlewis]

Streaming snapshots inadvertently removed Raft-initiated snapshot status
reporting. This is a feature that allows Raft to perform some IO
optimizations, according to the etcd Raft README, so we'd like to
continue using it.

Fixes #9592.

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This change is

[tamird]

Reviewed 1 of 1 files at r1.
Review status: all files reviewed at latest revision, 1 unresolved discussion, some commit checks pending.

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storage/replica.go, line 2386 at r1 (raw file):

              // Report the snapshot status to Raft, which expects us to do this once
              // we finish attempting to send the snapshot.
              r.reportSnapshotStatus(msg.To, err)

there's a TODO on the method that you should remove as part of this change.

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Comments from Reviewable

[petermattis]

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Review status: all files reviewed at latest revision, 1 unresolved discussion, all commit checks successful.

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Comments from Reviewable

[jordanlewis]

Review status: 0 of 1 files reviewed at latest revision, 1 unresolved discussion.

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storage/replica.go, line 2386 at r1 (raw file):

Previously, tamird (Tamir Duberstein) wrote…

there's a TODO on the method that you should remove as part of this change.

Done.

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Comments from Reviewable

[tamird]

modulo ongoing discussion in #9592.

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Reviewed 1 of 1 files at r2.
Review status: all files reviewed at latest revision, all discussions resolved, all commit checks successful.

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Comments from Reviewable