Have get nakamoto headers return only the unique block ids and increase the reward length

Signed-off-by: Jacinta Ferrant <[email protected]>

Author: jferrant

testnet/stacks-node/src/tests/signer/v0.rs

@@ -1481,6 +1481,7 @@ fn multiple_miners() {
             config.node.p2p_address = format!("{localhost}:{node_1_p2p}");
             config.miner.wait_on_interim_blocks = Duration::from_secs(5);
             config.node.pox_sync_sample_secs = 30;
+            config.burnchain.pox_reward_length = Some(30);
 
             config.node.seed = btc_miner_1_seed.clone();
             config.node.local_peer_seed = btc_miner_1_seed.clone();
@@ -1664,7 +1665,7 @@ fn multiple_miners() {
 /// Read processed nakamoto block IDs from the test observer, and use `config` to open
 ///  a chainstate DB and returns their corresponding StacksHeaderInfos
 fn get_nakamoto_headers(config: &Config) -> Vec<StacksHeaderInfo> {
-    let nakamoto_block_ids: Vec<_> = test_observer::get_blocks()
+    let nakamoto_block_ids: HashSet<_> = test_observer::get_blocks()
         .into_iter()
         .filter_map(|block_json| {
             if block_json