### 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
client().performRequest(updateSettingsRequest);
            Request shrinkIndexRequest = new Request("PUT", "/" + index + "/_shrink/" + shrunkenIndex);
            shrinkIndexRequest.setJsonEntity("{\"settings\": {\"index.number_of_shards\": 1}}");
            client().performRequest(shrinkIndexRequest);
            numDocs = countOfIndexedRandomDocuments();
        }
        refreshAllIndices();
        Map<?, ?> response = entityAsMap(client().performRequest(new Request("GET", "/" + index + "/_search")));
        assertNoFailures(response);
        int totalShards = (int) XContentMapValues.extractValue("_shards.total", response);
        assertThat(totalShards, greaterThan(1));
        int successfulShards = (int) XContentMapValues.extractValue("_shards.successful", response);
        assertEquals(totalShards, successfulShards);
        int totalHits = extractTotalHits(response);
        assertEquals(numDocs, totalHits);
        if (isRunningAgainstOldCluster() == false) {
            response = entityAsMap(client().performRequest(new Request("GET", "/" + shrunkenIndex + "/_search")));
            assertNoFailures(response);
            totalShards = (int) XContentMapValues.extractValue("_shards.total", response);
            assertEquals(1, totalShards);
            successfulShards = (int) XContentMapValues.extractValue("_shards.successful", response);
            assertEquals(1, successfulShards);
            totalHits = extractTotalHits(response);
            assertEquals(numDocs, totalHits);
        }
    }
    /**
     * Test upgrading after a rollover. Specifically:
     * <ol>
     *  <li>Create an index with a write alias