Include BSON type information in the Event metadata to allow for conversions

[dlvenable]

Example DocumentDB document:

{
  _id: Timestamp(time=1713536835 ordinal=12), 
  url: "https://github.com/opensearch-project/OpenSearch"
}

The source outputs:

{
  docdb_id: 1713536835, 
  url: "https://github.com/opensearch-project/OpenSearch"
}

metadata {
  "primary_key" : "1713536835-12",
  "documentdb_id_bson_type" : "timestamp"
}

[dlvenable]

Resolved by #4506