Mute MoreExpressionIT.testSpecialValueVariable (#10388)

Mute the test only for the concurrent search enabled case. See #10079.

Signed-off-by: Andrew Ross <andrross@amazon.com>

modules/lang-expression/src/internalClusterTest/java/org/opensearch/script/expression/MoreExpressionIT.java

@@ -504,6 +504,10 @@ public void testInvalidFieldMember() {
     }
 
     public void testSpecialValueVariable() throws Exception {
+        assumeFalse(
+            "Concurrent search case muted pending fix: https://github.com/opensearch-project/OpenSearch/issues/10079",
+            internalCluster().clusterService().getClusterSettings().get(CLUSTER_CONCURRENT_SEGMENT_SEARCH_SETTING)
+        );
         // i.e. _value for aggregations
         createIndex("test");
         ensureGreen("test");