Tag WorkCoordinatorTest as isolated after observing failues with simu…

…ltaneous test runs

Signed-off-by: Andre Kurait <[email protected]>

RFS/src/test/java/org/opensearch/migrations/bulkload/workcoordination/WorkCoordinatorTest.java

@@ -42,7 +42,7 @@
  * GET call to find out the new expiration value.
  */
 @Slf4j
-@Tag("longTest")
+@Tag("isolatedTest")
 public class WorkCoordinatorTest {
 
     public static final String DUMMY_FINISHED_DOC_ID = "dummy_finished_doc";