Wait for initial traces before starting tests

to ensure a late reported trace doesn’t mess up the test assertions.

dd-java-agent/instrumentation/elasticsearch-transport-2/src/test/groovy/Elasticsearch2NodeClientTest.groovy

@@ -40,6 +40,7 @@ class Elasticsearch2NodeClientTest extends AgentTestRunner {
     testNode = NodeBuilder.newInstance().clusterName("test-cluster").settings(settings).build()
     testNode.start()
     testNode.client().admin().cluster().prepareHealth().setWaitForYellowStatus().execute().actionGet(5000)
+    TEST_WRITER.waitForTraces(1)
   }
 
   def cleanupSpec() {

dd-java-agent/instrumentation/elasticsearch-transport-2/src/test/groovy/Elasticsearch2TransportClientTest.groovy

@@ -51,6 +51,7 @@ class Elasticsearch2TransportClientTest extends AgentTestRunner {
     ).build()
     client.addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("localhost"), TCP_PORT))
     client.admin().cluster().prepareHealth().setWaitForYellowStatus().execute().actionGet(5000)
+    TEST_WRITER.waitForTraces(1)
   }
 
   def cleanupSpec() {

dd-java-agent/instrumentation/elasticsearch-transport-5/src/test/groovy/Elasticsearch5NodeClientTest.groovy

@@ -46,6 +46,7 @@ class Elasticsearch5NodeClientTest extends AgentTestRunner {
     testNode = new Node(new Environment(InternalSettingsPreparer.prepareSettings(settings)), [Netty3Plugin])
     testNode.start()
     testNode.client().admin().cluster().prepareHealth().setWaitForYellowStatus().execute().actionGet(5000)
+    TEST_WRITER.waitForTraces(1)
   }
 
   def cleanupSpec() {

dd-java-agent/instrumentation/elasticsearch-transport-5/src/test/groovy/Elasticsearch5TransportClientTest.groovy

@@ -58,6 +58,7 @@ class Elasticsearch5TransportClientTest extends AgentTestRunner {
     )
     client.addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("localhost"), TCP_PORT))
     client.admin().cluster().prepareHealth().setWaitForYellowStatus().execute().actionGet(5000)
+    TEST_WRITER.waitForTraces(1)
   }
 
   def cleanupSpec() {

dd-java-agent/instrumentation/elasticsearch-transport-6/src/test/groovy/Elasticsearch6NodeClientTest.groovy

@@ -43,6 +43,7 @@ class Elasticsearch6NodeClientTest extends AgentTestRunner {
     testNode = new Node(InternalSettingsPreparer.prepareEnvironment(settings, null), [Netty4Plugin])
     testNode.start()
     testNode.client().admin().cluster().prepareHealth().setWaitForYellowStatus().execute().actionGet(5000)
+    TEST_WRITER.waitForTraces(1)
   }
 
   def cleanupSpec() {

dd-java-agent/instrumentation/elasticsearch-transport-6/src/test/groovy/Elasticsearch6TransportClientTest.groovy

@@ -55,6 +55,7 @@ class Elasticsearch6TransportClientTest extends AgentTestRunner {
     )
     client.addTransportAddress(new TransportAddress(InetAddress.getByName("localhost"), TCP_PORT))
     client.admin().cluster().prepareHealth().setWaitForYellowStatus().execute().actionGet(5000)
+    TEST_WRITER.waitForTraces(1)
   }
 
   def cleanupSpec() {