Fix basic auth integration test (#15679)

* Add some retries

* Add a delay to allow creds to propagate

* Checkstyle and stuff

integration-tests/src/test/java/org/apache/druid/tests/security/ITBasicAuthConfigurationTest.java

@@ -77,6 +77,20 @@ public class ITBasicAuthConfigurationTest extends AbstractAuthConfigurationTest
     checkNodeAccess(druid99);
   }
 
+  @Override
+  protected void setupHttpClientsAndUsers() throws Exception
+  {
+    super.setupHttpClientsAndUsers();
+
+    // Add a delay to allow propagation of credentials to all services
+    try {
+      Thread.sleep(5000);
+    }
+    catch (Throwable t) {
+      // Ignore exception
+    }
+  }
+
   @Override
   protected void setupDatasourceOnlyUser() throws Exception
   {