[MongoDB Persistence] Fix date query.

Issues:
- Second should have been getEndDate, not getBeginDate
- Send a Date object as the other version wasn't serializable.
- EndDate would have overridden beginDate.

Fixes openhab#10574

Signed-off-by: Stephan Brunner <s.brunner@stephan-brunner.net>

bundles/org.openhab.persistence.mongodb/src/main/java/org/openhab/persistence/mongodb/internal/MongoDBPersistenceService.java

@@ -339,11 +339,16 @@ public Iterable<HistoricItem> query(FilterCriteria filter) {
             Object value = convertValue(filter.getState());
             query.put(FIELD_VALUE, new BasicDBObject(op, value));
         }
+
+        BasicDBObject dateQueries = new BasicDBObject();
         if (filter.getBeginDate() != null) {
             dateQueries.put("$gte", Date.from(filter.getBeginDate().toInstant()));
         }
-        if (filter.getBeginDate() != null) {
-            query.put(FIELD_TIMESTAMP, new BasicDBObject("$lte", filter.getBeginDate()));
+        if (filter.getEndDate() != null) {
+            dateQueries.put("$lte", Date.from(filter.getEndDate().toInstant()));
+        }
+        if (!dateQueries.isEmpty()) {
+            query.put(FIELD_TIMESTAMP, dateQueries);
         }
 
         Integer sortDir = (filter.getOrdering() == Ordering.ASCENDING) ? 1 : -1;