debug: execute in message thread

Author: bevzzz

src/test/java/io/weaviate/client6/v1/api/collections/batch/BatchContextTest.java

@@ -138,11 +138,14 @@ public void reset() throws Exception {
     // This resets the interrupted flag, allowing use to await the executors.
     Thread.interrupted();
 
+    boolean terminated;
     backgroundThread.shutdownNow();
-    backgroundThread.awaitTermination(10, TimeUnit.SECONDS);
+    terminated = backgroundThread.awaitTermination(10, TimeUnit.SECONDS);
+    assert terminated : "backgroundThread not terminated";
 
     eventThread.shutdownNow();
-    eventThread.awaitTermination(10, TimeUnit.SECONDS);
+    terminated = eventThread.awaitTermination(10, TimeUnit.SECONDS);
+    assert terminated : "eventThread not terminated";
 
     REQUEST_QUEUE.clear();
 
@@ -185,7 +188,7 @@ public void test_sendOneBatch() throws Exception {
     Assertions.assertThat(tasks)
         .extracting(TaskHandle::isAcked).allMatch(CompletableFuture::isDone);
 
-    out.emitEvent(new Event.Results(received, Collections.emptyMap())).get();
+    out.stream.onNext(new Event.Results(received, Collections.emptyMap()));
 
     // Since MockServer runs in the same thread as this test,
     // the context will be updated before the last emitEvent returns.