### CI Link

https://gradle-enterprise.elastic.co/s/oyi6h23yl6k3o/tests/:x-pack:qa:full-cluster-restart:v8.11.0%23bwcTest/org.elasticsearch.xpack.restart.CoreFullClusterRestartIT/testClusterState%20%7Bcluster=OLD%7D

### Repro line

./gradlew ':qa:full-cluster-restart:v8.11.0#bwcTest' -Dtests.class="org.elasticsearch.upgrades.FullClusterRestartIT"

### Does it reproduce?

Yes

### Applicable branches

main

### Failure history

_No response_

### Failure excerpt

This test assumes that the index created version in cluster state matches the old node version.

That is no longer true due to the introduction of `IndexVersion`

https://github.com/elastic/elasticsearch/blob/52a6820813577abcb23191d862a01e32e652ed42/qa/full-cluster-restart/src/javaRestTest/java/org/elasticsearch/upgrades/FullClusterRestartIT.java#L435-L440
qa/full-cluster-restart/src/javaRestTest/java/org/elasticsearch/upgrades/FullClusterRestartIT.java
assertEquals("1", numberOfShards);
        numberOfReplicas = (String) XContentMapValues.extractValue(
            "metadata.indices." + index + ".settings.index.number_of_replicas",
            clusterState
        );
        assertEquals("0", numberOfReplicas);
        Version version = Version.fromId(
            Integer.valueOf(
                (String) XContentMapValues.extractValue("metadata.indices." + index + ".settings.index.version.created", clusterState)
            )
        );
        assertEquals(getOldClusterVersion(), version);
    }
    public void testShrink() throws IOException {
        String shrunkenIndex = index + "_shrunk";
        int numDocs;
        if (isRunningAgainstOldCluster()) {
            XContentBuilder mappingsAndSettings = jsonBuilder();
            mappingsAndSettings.startObject();
            {
                mappingsAndSettings.startObject("mappings");
                {
                    mappingsAndSettings.startObject("properties");
                    {
                        mappingsAndSettings.startObject("field");
                        {
                            mappingsAndSettings.field("type", "text");
                        }
                        mappingsAndSettings.endObject();
                    }