### 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/test/java/org/elasticsearch/index/mapper/CopyToMapperTests.java
b.endObject();
        }));
        MapperParsingException e = expectThrows(
            MapperParsingException.class,
            () -> docMapper.parse(source(b -> b.field("copy_test", "foo")))
        );
        assertThat(e.getMessage(), startsWith("mapping set to strict, dynamic introduction of [field] within [very.far] is not allowed"));
    }
    public void testCopyToFieldMerge() throws Exception {
        MapperService mapperService = createMapperService(mapping(b -> {
            b.startObject("copy_test");
            {
                b.field("type", "text");
                b.array("copy_to", "foo", "bar");
            }
            b.endObject();
        }));
        DocumentMapper docMapperBefore = mapperService.documentMapper();
        FieldMapper fieldMapperBefore = (FieldMapper) docMapperBefore.mappers().getMapper("copy_test");
        assertEquals(Arrays.asList("foo", "bar"), fieldMapperBefore.copyTo().copyToFields());
        merge(mapperService, mapping(b -> {
            b.startObject("copy_test");
            {
                b.field("type", "text");
                b.array("copy_to", "baz", "bar");
            }
            b.endObject();
        }));
        DocumentMapper docMapperAfter = mapperService.documentMapper();
        FieldMapper fieldMapperAfter = (FieldMapper) docMapperAfter.mappers().getMapper("copy_test");