GH-40775: [Benchmarking][Java] Fix conbench timeout

java/memory/memory-netty/src/test/java/org/apache/arrow/memory/netty/TestNettyAllocator.java

@@ -69,9 +69,12 @@ public void testMemoryUsage() {
           break;
         }
       }
-      assertTrue("Log messages are:\n" +
+      synchronized (memoryLogsAppender.list) {
+        assertTrue("Log messages are:\n" +
               memoryLogsAppender.list.stream().map(ILoggingEvent::toString).collect(Collectors.joining("\n")),
-          result);
+            result);
+      }
+
     } finally {
       memoryLogsAppender.stop();
       logger.detachAppender(memoryLogsAppender);

java/vector/src/main/java/org/apache/arrow/vector/ipc/WriteChannel.java

@@ -105,9 +105,6 @@ public long align() throws IOException {
    */
   public long write(ByteBuffer buffer) throws IOException {
     long length = buffer.remaining();
-    if (LOGGER.isDebugEnabled()) {
-      LOGGER.debug("Writing buffer with size: {}", length);
-    }
     while (buffer.hasRemaining()) {
       out.write(buffer);
     }