title: Spring Reactive MongoDB not saving document
body: <p>I'm trying to save a basic document but despite connecting to mongodb successfully... It doesn't seem to want to save. </p>
  
  <p><strong>Spring logs</strong></p>
  
  <pre><code>2018-10-03 00:17:25.998  INFO 10713 --- [  restartedMain] o.s.b.d.a.OptionalLiveReloadServer       : LiveReload server is running on port 35729
  2018-10-03 00:17:26.049  INFO 10713 --- [  restartedMain] o.s.j.e.a.AnnotationMBeanExporter        : Registering beans for JMX exposure on startup
  2018-10-03 00:17:26.106  INFO 10713 --- [ctor-http-nio-1] r.ipc.netty.tcp.BlockingNettyContext     : Started HttpServer on /0:0:0:0:0:0:0:0:8080
  2018-10-03 00:17:26.106  INFO 10713 --- [  restartedMain] o.s.b.web.embedded.netty.NettyWebServer  : Netty started on port(s): 8080
  2018-10-03 00:17:26.112  INFO 10713 --- [  restartedMain] c.l.s.ServiceLegalApplicationKt          : Started ServiceLegalApplicationKt in 3.459 seconds (JVM running for 4.201)
  2018-10-03 00:17:26.644  INFO 10713 --- [ntLoopGroup-2-2] org.mongodb.driver.connection            : Opened connection [connectionId{localValue:3, serverValue:4}] to localhost:27017
  </code></pre>
  
  <p><strong>application.properties</strong></p>
  
  <pre><code>spring.data.mongodb.host=localhost
  spring.data.mongodb.port=27017
  spring.data.mongodb.database=legal
  spring.data.mongodb.repositories.type=reactive
  spring.mongodb.embedded.version=4.0.2
  </code></pre>
  
  <p><strong>basic interface and class</strong></p>
  
  <pre><code>interface EventRepository: ReactiveMongoRepository&lt;Event, String&gt;
  
  @Document
  class Event(id: String, name: String)
  </code></pre>
  
  <p><strong>trying a simple save function</strong></p>
  
  <pre><code>@Service
  class SomeService(val eventRepository: EventRepository)
  {
      fun save() = eventRepository.save(Event(UUID.randomUUID().toString(), "hey"))
  }
  </code></pre>