Fix flaky test

Signed-off-by: Prudhvi Godithi <pgodithi@amazon.com>

Author: prudhvigodithi

server/src/internalClusterTest/java/org/opensearch/search/simple/SimpleSearchIT.java

@@ -432,7 +432,13 @@ public void doTestSimpleTerminateAfterTrackTotalHitsUpTo(int size) throws Except
             .setTrackTotalHitsUpTo(5)
             .get();
         assertEquals(5, searchResponse.getHits().getTotalHits().value());
-        assertEquals(GREATER_THAN_OR_EQUAL_TO, searchResponse.getHits().getTotalHits().relation());
+        // With approximation on LONG fields, if size < trackTotalHitsUpTo (5), we can efficiently determine the exact count and return
+        // EQUAL_TO relation.
+        if (size < 5) {
+            assertEquals(EQUAL_TO, searchResponse.getHits().getTotalHits().relation());
+        } else {
+            assertEquals(GREATER_THAN_OR_EQUAL_TO, searchResponse.getHits().getTotalHits().relation());
+        }
     }
 
     public void testSimpleTerminateAfterTrackTotalHitsUpToRandomSize0() throws Exception {