logicalType date not correctly indexed

We are using the opensearch connector to sink AVRO records to elasticsearch.

Our AVRO schema looks like this.
```
{
"type": "record",
"name": "Task",
"fields": [
{
"name": "id",
"type": "string"
},
{
"name": "assigned_to",
"type": "string"
},
{
"name": "deadline",
"type": [
"null",
{
"type": "int",
"name": "org.apache.kafka.connect.data.Date",
"logicalType": "date"
}
],
"default": null
}
]
}

```
The mapping of the deadline property in opensearch is correct
```
"deadline": {
"type": "date"
}
```
However, when indexing a record, the days since epoch value is sent to elasticsearch, which is not properly handled by opensearch

```
{
...,
"_source": {
"id": "7d9391d6-bc2c-44ce-868a-92095b9ebb01",
"assigned_to": "953e361e-2507-435e-afcf-4a060c958e97",
"deadline": 19594,
},
"fields": {
"deadline": [
"1970-01-01T00:00:19.594Z"
]
}
}
```