Add randomChoice option to weightedSwitchCotroller doc

Author: sebastianlorenzo88

docs/guide/request-generation/weighted-switch-controller.md

@@ -30,4 +30,33 @@ public class PerformanceTest {
 }
 ```
 
+By default `weightedSwitchController` will execute their children sequentially it is possible to change this behavior to execute them randomly by using `.randomChoice(true)`
+
+```java
+import static org.assertj.core.api.Assertions.assertThat;
+import static us.abstracta.jmeter.javadsl.JmeterDsl.*;
+
+import java.io.IOException;
+import java.time.Duration;
+import org.junit.jupiter.api.Test;
+import us.abstracta.jmeter.javadsl.core.TestPlanStats;
+
+public class PerformanceTest {
+
+  @Test
+  public void testPerformance() throws IOException {
+    TestPlanStats stats = testPlan(
+        threadGroup(2, 10,
+            weightedSwitchController()
+                .randomChoice(true) // will run children in a random way
+                .child(30, httpSampler("https://myservice/1")) 
+                .child(20, httpSampler("https://myservice/2"))
+        )
+    ).run();
+    assertThat(stats.overall().sampleTimePercentile99()).isLessThan(Duration.ofSeconds(5));
+  }
+
+}
+```
+
 [DslWeightedSwitchController](/jmeter-java-dsl/src/main/java/us/abstracta/jmeter/javadsl/core/controllers/DslWeightedSwitchController.java) for more details.