Simplify DateTimeType handling for Java Persistence API

Signed-off-by: Jacob Laursen <[email protected]>

Author: jlaur

bundles/org.openhab.persistence.jpa/src/main/java/org/openhab/persistence/jpa/internal/JpaHistoricItem.java

@@ -142,8 +142,7 @@ public static List<HistoricItem> fromResultList(List<JpaPersistentItem> jpaQuery
         } else if (item instanceof RollershutterItem) {
             state = PercentType.valueOf(pItem.getValue());
         } else if (item instanceof DateTimeItem) {
-            state = new DateTimeType(ZonedDateTime.ofInstant(Instant.ofEpochMilli(Long.parseLong(pItem.getValue())),
-                    ZoneId.systemDefault()));
+            state = new DateTimeType(Instant.ofEpochMilli(Long.parseLong(pItem.getValue())));
         } else if (item instanceof LocationItem) {
             PointType pType = null;
             String[] comps = pItem.getValue().split(";");

bundles/org.openhab.persistence.jpa/src/main/java/org/openhab/persistence/jpa/internal/StateHelper.java

@@ -37,7 +37,7 @@ public class StateHelper {
      */
     public static String toString(State state) {
         if (state instanceof DateTimeType type) {
-            return String.valueOf(type.getZonedDateTime().toInstant().toEpochMilli());
+            return String.valueOf(type.getInstant().toEpochMilli());
         }
         if (state instanceof DecimalType type) {
             return String.valueOf(type.doubleValue());