Improved: Could not find PortalPage with portalPageId []  (OFBIZ-13071)

When a spider bot gets to certain non-sense URIs under sfa app (it seems only
for sfa, did not dig further it's non-sense anyway) like discovered in
trunk demo log today: <</sfa/control/setSessionTimeZone?tzId=America/Ensenada>>
the <<Could not find PortalPage with portalPageId []>> error shows

Then we don't need to clutter the log with useless error information.
This keeps it ASAP by simply returning the portalPage if it's null.
diff --git a/framework/widget/src/main/java/org/apache/ofbiz/widget/model/ModelScreenWidget.java b/framework/widget/src/main/java/org/apache/ofbiz/widget/model/ModelScreenWidget.java
index fd38ba1..b05c19d 100644
--- a/framework/widget/src/main/java/org/apache/ofbiz/widget/model/ModelScreenWidget.java
+++ b/framework/widget/src/main/java/org/apache/ofbiz/widget/model/ModelScreenWidget.java
@@ -1947,7 +1947,6 @@
             if (portalPage == null) {
                 String errMsg = "Could not find PortalPage with portalPageId [" + expandedPortalPageId + "] ";
                 Debug.logError(errMsg, MODULE);
-                throw new RuntimeException(errMsg);
             }
             return portalPage;
         }