disable assertion jvm arg work around

Author: martijnvg

qa/mixed-cluster/build.gradle

@@ -90,6 +90,9 @@ buildParams.bwcVersions.withWireCompatible { bwcVersion, baseName ->
       if (bwcVersion.onOrAfter(Version.fromString("8.4.0"))) {
         setting 'health.master_history.no_master_transitions_threshold', '10'
       }
+      // TODO: conditionally add jvmarg based on old version
+      // Avoid tripping assertion on old nodes:
+      jvmArgs '-da:org.elasticsearch.index.mapper.DocumentMapper'
       requiresFeature 'es.index_mode_feature_flag_registered', Version.fromString("8.0.0")
     }
 

x-pack/plugin/downsample/qa/mixed-cluster/src/yamlRestTest/java/org/elasticsearch/xpack/downsample/MixedClusterDownsampleRestIT.java

@@ -25,6 +25,9 @@ public class MixedClusterDownsampleRestIT extends ESClientYamlSuiteTestCase {
         .withNode(node -> node.version(Version.CURRENT))
         .setting("xpack.security.enabled", "false")
         .setting("xpack.license.self_generated.type", "trial")
+        // TODO: conditionally add jvmarg based on old version
+        // Avoid tripping assertion on old nodes:
+        .jvmArg("-da:org.elasticsearch.index.mapper.DocumentMapper")
         .build();
 
     static Version getOldVersion() {

x-pack/plugin/esql/qa/server/mixed-cluster/src/javaRestTest/java/org/elasticsearch/xpack/esql/qa/mixed/Clusters.java

@@ -23,6 +23,9 @@ public static ElasticsearchCluster mixedVersionCluster() {
             .setting("xpack.security.enabled", "false")
             .setting("xpack.license.self_generated.type", "trial")
             .setting("cluster.routing.rebalance.enable", "none") // disable relocation until we have retry in ESQL
+            // TODO: conditionally add jvmarg based on old version
+            // Avoid tripping assertion on old nodes:
+            .jvmArg("-da:org.elasticsearch.index.mapper.DocumentMapper")
             .build();
     }
 }