Use least-leaders for default leader locator strategy

References rabbitmq/rabbitmq-server#4442.

References #110

Author: acogoluegnes

src/main/java/com/rabbitmq/stream/StreamCreator.java

@@ -80,6 +80,8 @@ enum LeaderLocator {
      * overall less than 1000 queues, or a random node, if there are overall more than 1000 queues.
      *
      * <p>Available as of RabbitMQ 3.10.
+     *
+     * Default value for RabbitMQ 3.10+.
      */
     BALANCED("balanced"),
 
@@ -94,6 +96,8 @@ enum LeaderLocator {
      * The stream leader will be on the node with the least number of stream leaders.
      *
      * <p>Deprecated as of RabbitMQ 3.10, same as {@link LeaderLocator#BALANCED}.
+     *
+     * Default value for RabbitMQ 3.9.
      */
     LEAST_LEADERS("least-leaders");
 

src/main/java/com/rabbitmq/stream/impl/StreamStreamCreator.java

@@ -25,7 +25,7 @@ class StreamStreamCreator implements StreamCreator {
 
   private final StreamEnvironment environment;
   private final Client.StreamParametersBuilder streamParametersBuilder =
-      new Client.StreamParametersBuilder().leaderLocator(LeaderLocator.CLIENT_LOCAL);
+      new Client.StreamParametersBuilder().leaderLocator(LeaderLocator.LEAST_LEADERS);
   private String stream;
 
   StreamStreamCreator(StreamEnvironment environment) {

src/main/java/com/rabbitmq/stream/perf/StreamPerfTest.java

@@ -241,7 +241,7 @@ public class StreamPerfTest implements Callable<Integer> {
           "leader locator strategy for created stream. "
               + "Possible values: client-local, balanced (RabbitMQ 3.10), least-leaders, random.",
       converter = Utils.LeaderLocatorTypeConverter.class,
-      defaultValue = "client-local")
+      defaultValue = "least-leaders")
   private LeaderLocator leaderLocator;
 
   @CommandLine.Option(