fix: do not log complete stream. (#2258)

Log the hashCode instead of toString to avoid dumping all the file content in memory and in log because of https://github.com/apache/cxf/blob/main/core/src/main/java/org/apache/cxf/io/CachedOutputStream.java#L423
This cause OOM on our app.

core/src/main/java/org/apache/cxf/io/DelayedCachedOutputStreamCleaner.java

@@ -119,7 +119,7 @@ private void clean(Collection<DelayedCloseable> closeables) {
                 final DelayedCloseable next = iterator.next();
                 try {
                     iterator.remove();
-                    LOG.warning("Unclosed (leaked?) stream detected: " + next.closeable);
+                    LOG.warning("Unclosed (leaked?) stream detected: " + next.closeable.hashCode());
                     next.closeable.close();
                 } catch (final IOException | RuntimeException ex) {
                     LOG.warning("Unable to close (leaked?) stream: " + ex.getMessage());