Fix java date parsing to be compatible with joda (#36155)

ZonedDateTime toString format yyyy-MM-ddTHH:mmZ is failing parsing by
our java-time DateFormatters whereas it passes Joda parsing. The pattern
is strict_date_optional_time||epoch_millis

Author: pgomulka

server/src/main/java/org/elasticsearch/common/time/DateFormatters.java

@@ -85,13 +85,13 @@ public class DateFormatters {
         .optionalStart()
         .appendFraction(MILLI_OF_SECOND, 3, 3, true)
         .optionalEnd()
+        .optionalEnd()
         .optionalStart()
         .appendZoneOrOffsetId()
         .optionalEnd()
         .optionalEnd()
         .optionalEnd()
         .optionalEnd()
-        .optionalEnd()
         .toFormatter(Locale.ROOT);
 
     private static final DateTimeFormatter STRICT_DATE_OPTIONAL_TIME_FORMATTER_2 = new DateTimeFormatterBuilder()

server/src/test/java/org/elasticsearch/common/joda/JavaJodaTimeDuellingTests.java

@@ -286,6 +286,7 @@ public void testDuelingStrictParsing() {
         assertParseException("2018-12-31T10:15:3", "strict_date_optional_time");
         assertParseException("2018-12-31T10:5:30", "strict_date_optional_time");
         assertParseException("2018-12-31T9:15:30", "strict_date_optional_time");
+        assertSameDate("2015-01-04T00:00Z", "strict_date_optional_time");
         assertSameDate("2018-12-31T10:15:30.123Z", "strict_date_time");
         assertSameDate("2018-12-31T10:15:30.11Z", "strict_date_time");
         assertParseException("2018-12-31T10:15:3.123Z", "strict_date_time");