Example didn't demonstrate null long case

It demonstrated that AsOptional<Long> could be composed
over a primitive AsLong adapter, and return non-null
values, but the query wasn't updated to supply a null
array element to demonstrate the other case, which
naturally also works, but the example ought to show it.

pljava-examples/src/main/java/org/postgresql/pljava/example/annotation/TupleTableSlotTest.java

@@ -135,7 +135,7 @@ public static Iterator<String> javaMultiArrayTest()
 			" CAST ( '{{{{{t},{f},{t}}}}}'   AS     boolean [] ), " +
 			" CAST ( '{{{{''epoch''}}}}'     AS timestamptz [] )  " +
 			"), (" +
-			" NULL, NULL, NULL, NULL, '{{{{{1,NULL,3}}}}}', NULL, NULL," +
+			" '{NULL}', NULL, NULL, NULL, '{{{{{1,NULL,3}}}}}', NULL, NULL," +
 			" '{{{{NULL}}}}'" +
 			")";