[tiny] Fix histogram metric, reduce warning volume (MystenLabs#9858)

1. The histogram for calculating round duration didn't convert it from
ms to sec
2. We shouldn't generate a warn message for the long standing user cert
sequencing, it might creates unhealthy volume of unnecessary logs.

## Description 

Describe the changes or additions included in this PR.

## Test Plan 

How did you test the new or updated feature?

---
If your changes are not user-facing and not a breaking change, you can
skip the following section. Otherwise, please indicate what changed, and
then add to the Release Notes section as highlighted during the release
process.

### Type of Change (Check all that apply)

- [ ] user-visible impact
- [ ] breaking change for a client SDKs
- [ ] breaking change for FNs (FN binary must upgrade)
- [ ] breaking change for validators or node operators (must upgrade
binaries)
- [ ] breaking change for on-chain data layout
- [ ] necessitate either a data wipe or data migration

### Release notes

Co-authored-by: Dmitri Perelman <[email protected]>

crates/sui-core/src/consensus_adapter.rs

@@ -569,16 +569,25 @@ impl ConsensusAdapter {
             Either::Right(((), processed_waiter)) => Some(processed_waiter),
         };
         let transaction_key = transaction.key();
-        let _monitor = CancelOnDrop(spawn_monitored_task!(async {
-            let mut i = 0u64;
-            loop {
-                i += 1;
-                const WARN_DELAY_S: u64 = 30;
-                tokio::time::sleep(Duration::from_secs(WARN_DELAY_S)).await;
-                let total_wait = i * WARN_DELAY_S;
-                warn!("Still waiting {total_wait} seconds for transaction {transaction_key:?} to commit in narwhal");
-            }
-        }));
+        // Log warnings for capability or end of publish transactions that fail to get sequenced
+        let _monitor = if matches!(
+            transaction.kind,
+            ConsensusTransactionKind::EndOfPublish(_)
+                | ConsensusTransactionKind::CapabilityNotification(_)
+        ) {
+            Some(CancelOnDrop(spawn_monitored_task!(async {
+                let mut i = 0u64;
+                loop {
+                    i += 1;
+                    const WARN_DELAY_S: u64 = 30;
+                    tokio::time::sleep(Duration::from_secs(WARN_DELAY_S)).await;
+                    let total_wait = i * WARN_DELAY_S;
+                    warn!("Still waiting {total_wait} seconds for transaction {transaction_key:?} to commit in narwhal");
+                }
+            })))
+        } else {
+            None
+        };
         if let Some(processed_waiter) = processed_waiter {
             debug!("Submitting {transaction_key:?} to consensus");
 

narwhal/primary/src/proposer.rs

@@ -475,7 +475,7 @@ impl Proposer {
                     self.metrics
                         .proposal_latency
                         .with_label_values(&[reason])
-                        .observe((current_timestamp - t) as f64);
+                        .observe(((current_timestamp - t) / 1000) as f64);
                 }
                 self.last_round_timestamp = Some(current_timestamp);
                 debug!("Dag moved to round {}", self.round);