### Elasticsearch Version

master

### Installed Plugins

N/A

### Java Version

_bundled_

### OS Version

N/A

### Problem Description

@arteam [observed](https://github.com/elastic/elasticsearch/pull/83221/files#r795474431) that `static record` is redundant, records are apparently implicitly static. I think we should make sure that Checkstyle picks this up rather than needing human involvement.

### Steps to Reproduce

Mark a record declaration as `static` and observe that `./gradlew precommit` still passes.

### Logs (if relevant)

_No response_
server/src/main/java/org/elasticsearch/cluster/routing/IndexRouting.java
default:
                    throw new ParsingException(
                        source.getTokenLocation(),
                        "Routing values must be strings but found [{}]",
                        source.currentToken()
                    );
            }
        }
        private int hashSource(Map<String, Object> flat) {
            List<NameAndHash> hashes = new ArrayList<>();
            for (Map.Entry<String, Object> e : flat.entrySet()) {
                if (Regex.simpleMatch(routingPaths, e.getKey())) {
                    hashes.add(new NameAndHash(new BytesRef(e.getKey()), hash(new BytesRef(e.getValue().toString()))));
                }
            }
            return hashesToHash(hashes);
        }
        private static int hash(BytesRef ref) {
            return StringHelper.murmurhash3_x86_32(ref, 0);
        }
        private static int hashesToHash(List<NameAndHash> hashes) {
            Collections.sort(hashes);
            Iterator<NameAndHash> itr = hashes.iterator();
            if (itr.hasNext() == false) {
                throw new IllegalArgumentException("Error extracting routing: source didn't contain any routing fields");
            }
            NameAndHash prev = itr.next();
            int hash = hash(prev.name) ^ prev.hash;
            while (itr.hasNext()) {
                NameAndHash next = itr.next();