Owls 97601 - Changes to prevent pod roll when upgrading operator 3.3.8 to 3.4 (#2850)

* OWLS-97601 - Changes to prevent pod roll during operator 3.3.8 to 3.4 upgrade.

Author: ankedia

operator/src/main/java/oracle/kubernetes/operator/helpers/PodStepContext.java

@@ -94,7 +94,9 @@
 import static oracle.kubernetes.operator.helpers.EventHelper.EventItem.DOMAIN_ROLL_STARTING;
 import static oracle.kubernetes.operator.helpers.EventHelper.EventItem.POD_CYCLE_STARTING;
 import static oracle.kubernetes.operator.helpers.LegalNames.LEGAL_CONTAINER_PORT_NAME_MAX_LENGTH;
+import static oracle.kubernetes.utils.OperatorUtils.isNullOrEmpty;
 import static oracle.kubernetes.weblogic.domain.model.Model.DEFAULT_WDT_INSTALL_HOME;
+import static oracle.kubernetes.weblogic.domain.model.Model.DEFAULT_WDT_MODEL_HOME;
 
 public abstract class PodStepContext extends BasePodStepContext {
 
@@ -963,9 +965,13 @@ void addStartupEnvVars(List<V1EnvVar> vars, TuningParameters tuningParameters) {
     addEnvVar(vars, ServerEnvVars.AS_SERVICE_NAME, LegalNames.toServerServiceName(getDomainUid(), getAsName()));
     Optional.ofNullable(getDataHome()).ifPresent(v -> addEnvVar(vars, ServerEnvVars.DATA_HOME, v));
     String wdtInstallHome = getWdtInstallHome();
-    if (wdtInstallHome != null && !wdtInstallHome.isEmpty() && !wdtInstallHome.equals(DEFAULT_WDT_INSTALL_HOME)) {
+    if (!isNullOrEmpty(wdtInstallHome) && !wdtInstallHome.equals(DEFAULT_WDT_INSTALL_HOME)) {
       addEnvVar(vars, IntrospectorJobEnvVars.WDT_INSTALL_HOME, wdtInstallHome);
     }
+    String modelHome = getModelHome();
+    if (!isNullOrEmpty(modelHome) && !modelHome.equals(DEFAULT_WDT_MODEL_HOME)) {
+      addEnvVar(vars, IntrospectorJobEnvVars.WDT_MODEL_HOME, modelHome);
+    }
     Optional.ofNullable(getServerSpec().getAuxiliaryImages()).ifPresent(cm -> addAuxiliaryImageEnv(cm, vars));
     addEnvVarIfTrue(mockWls(), vars, "MOCK_WLS");
     Optional.ofNullable(getKubernetesPlatform(tuningParameters)).ifPresent(v ->