### 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
ensureGreen(index);
            numDocs = Integer.parseInt(loadInfoDocument("num_doc_" + index));
            int moreDocs = randomIntBetween(0, 100);
            for (int i = 0; i < moreDocs; i++) {
                indexDocument(Integer.toString(numDocs + i));
                if (rarely()) {
                    flush(index, randomBoolean());
                }
            }
            Request updateSettingsRequest = new Request("PUT", "/" + index + "/_settings");
            updateSettingsRequest.setJsonEntity("{\"settings\": {\"index.blocks.write\": true}}");
            client().performRequest(updateSettingsRequest);
            {
                final String target = index + "_shrunken";
                Request shrinkRequest = new Request("PUT", "/" + index + "/_shrink/" + target);
                Settings.Builder settings = Settings.builder().put(IndexMetadata.SETTING_NUMBER_OF_SHARDS, 1);
                if (randomBoolean()) {
                    settings.put(IndexSettings.INDEX_SOFT_DELETES_SETTING.getKey(), true);
                }
                shrinkRequest.setJsonEntity("{\"settings\":" + Strings.toString(settings.build()) + "}");
                client().performRequest(shrinkRequest);
                ensureGreenLongWait(target);
                assertNumHits(target, numDocs + moreDocs, 1);
            }
            {
                final String target = index + "_split";
                Settings.Builder settings = Settings.builder().put(IndexMetadata.SETTING_NUMBER_OF_SHARDS, 6);
                if (randomBoolean()) {
                    settings.put(IndexSettings.INDEX_SOFT_DELETES_SETTING.getKey(), true);
                }