Make propritary fields not indexed #325

Description
Hi
I am trying to add some proprietary fields to the elastic serilog sink. But the fields should not be indexed.
I have created a template to use for this. But still the dynamic fields added with an enritcher using logEvent.AddOrUpdateProperty makes the fields indexed. Is there any way I can get this proprietary fields into ES where they are not indexed ?
"mappings": {
"default": {
"dynamic_templates": [
{
"string_fields": {
"match": "*",
"match_mapping_type": "string",
"mapping": {
"type": "text",
"index": false,
"norms": false,
"fields": {
"raw": {
"type": "keyword",
"index": false,
"ignore_above": 256
}
}
}
}
}
],
"properties": {
"message": {
"type": "text",
"index": true
},
"subject": {
"type": "text",
"index": true
},
"logger": {
"type": "text",
"index": true
},
}
}