Revert changes in test file

Author: krisztian-toth

samples/boot/oauth2login/src/integration-test/java/org/springframework/security/samples/OAuth2LoginApplicationTests.java

@@ -67,6 +67,7 @@
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.stream.Collectors;
 
@@ -330,14 +331,10 @@ private void assertIndexPage(HtmlPage page) throws Exception {
 	}
 
 	private HtmlAnchor getClientAnchorElement(HtmlPage page, ClientRegistration clientRegistration) {
-		HtmlAnchor result = null;
-		for (HtmlAnchor anchor: page.getAnchors()) {
-			if (anchor.asText().equals(clientRegistration.getClientName())) {
-				result = anchor;
-				break;
-			}
-		}
-		return result;
+		Optional<HtmlAnchor> clientAnchorElement = page.getAnchors().stream()
+				.filter(e -> e.asText().equals(clientRegistration.getClientName())).findFirst();
+
+		return (clientAnchorElement.orElse(null));
 	}
 
 	private WebResponse followLinkDisableRedirects(HtmlAnchor anchorElement) throws Exception {