Fix config normalization in ThingUpdatedEvent (#3157)

Signed-off-by: Jan N. Klug <github@klug.nrw>

bundles/org.openhab.core.thing/src/main/java/org/openhab/core/thing/internal/ThingManagerImpl.java

@@ -610,6 +610,7 @@ public class ThingManagerImpl
     @SuppressWarnings("PMD.CompareObjectsWithEquals")
     public void thingUpdated(Thing oldThing, Thing newThing, ThingTrackerEvent thingTrackerEvent) {
         ThingUID thingUID = newThing.getUID();
+        normalizeThingConfiguration(oldThing);
         normalizeThingConfiguration(newThing);
         if (thingUpdatedLock.contains(thingUID)) {
             // called from the thing handler itself, therefore