Cherry pick: [Consensus 2.0] Fix retries and wait time during fetch b…

…lock request timeout (#18034)

## Description 

Cherry pick of #18033

## Test plan 

How did you test the new or updated feature?

---

## Release notes

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your changes, release notes aren't required.

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that describes the impact of your changes that a user might notice and
any actions they must take to implement updates.

- [ ] Protocol: 
- [ ] Nodes (Validators and Full nodes): 
- [ ] Indexer: 
- [ ] JSON-RPC: 
- [ ] GraphQL: 
- [ ] CLI: 
- [ ] Rust SDK:

consensus/core/src/synchronizer.rs

@@ -612,6 +612,8 @@ impl<C: NetworkClient, V: BlockVerifier, D: CoreThreadDispatcher> Synchronizer<C
             } // network error
             Err(err) => {
                 // timeout
+                sleep_until(start + request_timeout).await;
+                retries += 1;
                 Err(ConsensusError::NetworkRequestTimeout(err.to_string()))
             }
             Ok(result) => result,