Make the tests server handle upserts properly #216

import com.mongodb.client.model.Filters
import com.mongodb.client.MongoClient

private val client: MongoClient = ...

...
        val data = mapOf("key1" to "value1", "key2" to "value2")
        val filter = Filters.and(data.map {
            Filters.eq(it.key, it.value)
        })
        client.getDatabase(db).getCollection(collection).updateOne(
            filter,
            Updates.set("dummy", "dummy"),
            UpdateOptions().upsert(true)
        )

            if (key.startsWith("$")) {
                continue;
            }