Fix GetStackTracesResponseTests

Author: rockdaboot

x-pack/plugin/profiling/src/test/java/org/elasticsearch/xpack/profiling/action/GetStackTracesResponseTests.java

@@ -55,8 +55,8 @@ private GetStackTracesResponse createTestInstance() {
 
     public void testChunking() {
         AbstractChunkedSerializingTestCase.assertChunkCount(createTestInstance(), instance -> {
-            // start, end, total_frames, samplingrate
-            int chunks = 4;
+            // start and {total_frames, sampling_rate; end}; see GetStackTracesResponse.toXContentChunked()
+            int chunks = 2;
             chunks += size(instance.getExecutables());
             chunks += size(instance.getStackFrames());
             chunks += size(instance.getStackTraces());