SecretEnricher getSecretsFromXmlConfig should return Collections.empt…

…yList() instead of null (#2610)

jkube-kit/enricher/generic/src/main/java/org/eclipse/jkube/enricher/generic/SecretEnricher.java

@@ -78,7 +78,7 @@ private void addSecretsFromXmlConfiguration(KubernetesListBuilder builder) {
         log.verbose("Adding secrets resources from plugin configuration");
         List<SecretConfig> secrets = getSecretsFromXmlConfig();
         Map<String, Integer> secretToIndexMap = new HashMap<>();
-        if (secrets == null || secrets.isEmpty()) {
+        if (secrets.isEmpty()) {
             return;
         }