Cypher: Use GMT for calculating the time intervals for IC3 and IC4

endDate = startDate + durationDays

Author: szarnyasg

cypher/src/main/java/org/ldbcouncil/snb/impls/workloads/cypher/CypherQueryStore.java

@@ -3,6 +3,7 @@
 import java.util.Calendar;
 import java.util.Date;
 import java.util.Map;
+import java.util.TimeZone;
 
 import com.google.common.collect.ImmutableMap;
 
@@ -25,7 +26,7 @@ protected Converter getConverter() {
 
     static protected Date addDays( Date startDate, int days )
     {
-        final Calendar cal = Calendar.getInstance();
+        final Calendar cal = Calendar.getInstance(TimeZone.getTimeZone("GMT"));
         cal.setTime( startDate );
         cal.add( Calendar.DATE, days );
         return cal.getTime();