Add missing ConditionalOnProperty

Author: LEDfan

src/main/java/eu/openanalytics/containerproxy/auth/impl/KeycloakAuthenticationBackend.java

@@ -173,6 +173,7 @@ protected SessionAuthenticationStrategy sessionAuthenticationStrategy() {
 	}
 
 	@Bean
+	@ConditionalOnProperty(name="proxy.authentication", havingValue="keycloak")
 	public KeycloakAuthenticationFailureHandler keycloakAuthenticationFailureHandler() {
 		return new AuthenticationFaillureHandler();
 	}