Avoid unnecessary metrics setup for buffered events (apache#4877)

Author: mj006648

runtime/service/src/test/java/org/apache/polaris/service/events/listeners/inmemory/InMemoryBufferEventListenerBufferSizeTest.java

@@ -24,6 +24,8 @@
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.doThrow;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
 
 import io.quarkus.test.junit.QuarkusTest;
 import io.quarkus.test.junit.TestProfile;
@@ -46,6 +48,7 @@ void testFlushOnSize() {
     sendAsync("test2", 10);
     assertRows("test1", 10);
     assertRows("test2", 10);
+    verify(metaStoreManagerFactory, never()).getOrCreateMetricsPersistence(any());
   }
 
   @Test