Promote GetNewBlockV3 and enable by default (#8493)

* Remove -X prefix

Signed-off-by: Gabriel Fukushima <gabrielfukushima@gmail.com>

* add changelog

Signed-off-by: Gabriel Fukushima <gabrielfukushima@gmail.com>

---------

Signed-off-by: Gabriel Fukushima <gabrielfukushima@gmail.com>

CHANGELOG.md

@@ -23,5 +23,6 @@
 - When `p2p-subscribe-all-subnets-enabled`, `p2p-peer-lower-bound` now defaults to 60 (previously 64), and `p2p-peer-upper-bound` now defaults to 80 (previously 100).
 - When `p2p-subscribe-all-subnets-enabled`,  (`Xnetwork-async-p2p-max-queue`, `Xnetwork-async-beaconchain-max-queue`, `Xp2p-batch-verify-signatures-queue-capacity`)  now default to 40_000 (previously 10_000)
 - When `p2p-subscribe-all-subnets-enabled`,  `Xvalidator-executor-max-queue-size`  now defaults to 60_000 (previously 40_000).
+- Enable [GetNewBlockV3](https://ethereum.github.io/beacon-APIs/?urls.primaryName=dev#/ValidatorRequiredApi/produceBlockV3) by default.  
 
 ### Bug Fixes

validator/api/src/main/java/tech/pegasys/teku/validator/api/ValidatorConfig.java

@@ -46,7 +46,7 @@ public class ValidatorConfig {
       List.of(URI.create("http://127.0.0.1:" + DEFAULT_REST_API_PORT));
   public static final boolean DEFAULT_FAILOVERS_SEND_SUBNET_SUBSCRIPTIONS_ENABLED = true;
   public static final boolean DEFAULT_FAILOVERS_PUBLISH_SIGNED_DUTIES_ENABLED = true;
-  public static final boolean DEFAULT_BLOCK_V3_ENABLED = false;
+  public static final boolean DEFAULT_BLOCK_V3_ENABLED = true;
   public static final boolean DEFAULT_EXIT_WHEN_NO_VALIDATOR_KEYS_ENABLED = false;
   public static final boolean DEFAULT_VALIDATOR_CLIENT_SSZ_BLOCKS_ENABLED = true;
   public static final boolean DEFAULT_VALIDATOR_CLIENT_USE_POST_VALIDATORS_ENDPOINT_ENABLED = true;