fix syntax

Author: ankit--sethi

x-pack/plugin/security/src/test/java/org/elasticsearch/xpack/security/authc/AuthenticatorChainTests.java

@@ -68,6 +68,7 @@ public class AuthenticatorChainTests extends ESTestCase {
     private OAuth2TokenAuthenticator oAuth2TokenAuthenticator;
     private ApiKeyAuthenticator apiKeyAuthenticator;
     private PluggableApiKeyAuthenticator pluggableApiKeyAuthenticator;
+    private PluggableOAuth2TokenAuthenticator pluggableOAuth2TokenAuthenticator;
     private RealmsAuthenticator realmsAuthenticator;
     private Authentication authentication;
     private User fallbackUser;
@@ -104,6 +105,7 @@ public void init() {
             anonymousUser,
             authenticationContextSerializer,
             serviceAccountAuthenticator,
+            pluggableOAuth2TokenAuthenticator,
             oAuth2TokenAuthenticator,
             pluggableApiKeyAuthenticator,
             apiKeyAuthenticator,