[fix][test] Remove useless test code (apache#23823)

Author: gaoran10

pulsar-broker/src/test/java/org/apache/pulsar/broker/intercept/ManagedLedgerInterceptorImplTest.java

@@ -470,7 +470,6 @@ public void release(ByteBuf processedPayload) {
         var addEntryCallback = new AsyncCallbacks.AddEntryCallback() {
             @Override
             public void addComplete(Position position, ByteBuf entryData, Object ctx) {
-                entryData.release();
                 countDownLatch.countDown();
                 successCount.incrementAndGet();
             }