Fix edge cases in CompositeKeyExtractorTests (#30175)

Currently the test picks random java.util.TimeZone ids in some places.
Internally we still need to convert back to joda DateTimeZone by id
occassionally (e.g. when serializing to pre 6.3 versions). There are
some deprecated "SystemV/*" time zones that Jodas DateTimeZone refuses
to convert. This change excludes those rare cases from the set of
allowed random time zones. It would be quiet odd for them to appear in
practice.

Closes #30156

x-pack/plugin/sql/src/test/java/org/elasticsearch/xpack/sql/execution/search/extractor/CompositeKeyExtractorTests.java

@@ -15,6 +15,7 @@
 import org.joda.time.DateTimeZone;
 
 import java.io.IOException;
+import java.util.TimeZone;
 
 import static java.util.Arrays.asList;
 import static java.util.Collections.emptyList;
@@ -24,7 +25,7 @@
 public class CompositeKeyExtractorTests extends AbstractWireSerializingTestCase<CompositeKeyExtractor> {
 
     public static CompositeKeyExtractor randomCompositeKeyExtractor() {
-        return new CompositeKeyExtractor(randomAlphaOfLength(16), randomFrom(asList(Property.values())), randomTimeZone());
+        return new CompositeKeyExtractor(randomAlphaOfLength(16), randomFrom(asList(Property.values())), randomSafeTimeZone());
     }
 
     @Override
@@ -58,7 +59,7 @@ public void testExtractKey() {
     }
 
     public void testExtractDate() {
-        CompositeKeyExtractor extractor = new CompositeKeyExtractor(randomAlphaOfLength(16), Property.VALUE, randomTimeZone());
+        CompositeKeyExtractor extractor = new CompositeKeyExtractor(randomAlphaOfLength(16), Property.VALUE, randomSafeTimeZone());
 
         long millis = System.currentTimeMillis();
         Bucket bucket = new TestBucket(singletonMap(extractor.key(), millis), randomLong(), new Aggregations(emptyList()));
@@ -73,4 +74,13 @@ public void testExtractIncorrectDateKey() {
         SqlIllegalArgumentException exception = expectThrows(SqlIllegalArgumentException.class, () -> extractor.extract(bucket));
         assertEquals("Invalid date key returned: " + value, exception.getMessage());
     }
+
+    /**
+     * We need to exclude SystemV/* time zones because they cannot be converted
+     * back to DateTimeZone which we currently still need to do internally,
+     * e.g. in bwc serialization and in the extract() method
+     */
+    private static TimeZone randomSafeTimeZone() {
+        return randomValueOtherThanMany(tz -> tz.getID().startsWith("SystemV"), () -> randomTimeZone());
+    }
 }