### Elasticsearch Version

8.2.0

### Installed Plugins

_No response_

### Java Version

_bundled_

### OS Version

docker-image = docker.elastic.co/elasticsearch/elasticsearch:8.2.0

### Problem Description

We are trying to migrate from Elasticsearch 6.7.1 to Elasticsearch 8.2.0.

With the same amount of documents per bulk request (100 docs per request), we always get a socket timeout in Elasticsearch 8.2.0. Everything works fine in Elasticsearch 6.7.1.

I noticed that indexing the same document in Elasticsearch 8.2.0 takes 44152ms. In Elasticsearch 6.7.1, indexing takes 50ms.

### Steps to Reproduce

[elasticsearch_8.2.0.txt](https://github.com/elastic/elasticsearch/files/8754299/elasticsearch_8.2.0.txt)
[elasticsearch_6.7.1.txt](https://github.com/elastic/elasticsearch/files/8754300/elasticsearch_6.7.1.txt)



### Logs (if relevant)

_No response_
server/src/main/java/org/elasticsearch/index/mapper/DocumentParser.java
if (token != XContentParser.Token.START_OBJECT) {
            throwNoStartOnObject();
        }
    }
    private static void throwNoStartOnObject() {
        throw new MapperParsingException("Malformed content, must start with an object");
    }
    private static void validateEnd(XContentParser parser) throws IOException {
        XContentParser.Token token;
        
        
        token = parser.nextToken();
        if (token != null) {
            throwNotAtEnd(token);
        }
    }
    private static void throwNotAtEnd(XContentParser.Token token) {
        throw new IllegalArgumentException("Malformed content, found extra data after parsing: " + token);
    }
    private static boolean isEmptyDoc(RootObjectMapper root, XContentParser parser) throws IOException {
        if (root.isEnabled()) {
            final XContentParser.Token token = parser.nextToken();
            switch (token) {
                case END_OBJECT:
                    
                    return true;
                case FIELD_NAME:
                    return false;
                default:
                    throwOnMalformedContent();