Once https://github.com/elastic/elasticsearch/issues/98503 is done, we can use our minimum version numbers in the SystemIndexMappingUpdate service instead of the old `Version` types. Mappings will be updated for a system index when all nodes have a matching descriptor mappings version for a system index, but this version is greater than what's stored in the mappings metadata.
server/src/test/java/org/elasticsearch/cluster/ClusterStateTests.java
IndexMetadata indexMetadata = IndexMetadata.builder("index")
            .state(IndexMetadata.State.OPEN)
            .settings(Settings.builder().put(SETTING_VERSION_CREATED, IndexVersion.current()))
            .putMapping(new MappingMetadata("type", new HashMap<>() {
                {
                    put("type1", new HashMap<String, Object>() {
                        {
                            put("key", "value");
                        }
                    });
                }
            }))
            .putAlias(AliasMetadata.builder("alias").indexRouting("indexRouting").build())
            .numberOfShards(1)
            .primaryTerm(0, 1L)
            .putInSyncAllocationIds(0, new HashSet<>() {
                {
                    add("allocationId");
                }
            })
            .numberOfReplicas(2)
            .putRolloverInfo(new RolloverInfo("rolloveAlias", new ArrayList<>(), 1L))
            .stats(new IndexMetadataStats(IndexWriteLoad.builder(1).build(), 120, 1))
            .indexWriteLoadForecast(8.0)
            .build();
        return ClusterState.builder(ClusterName.DEFAULT)
            .stateUUID("stateUUID")
            .nodes(
                DiscoveryNodes.builder()
                    .masterNodeId("nodeId1")