Race condition between Active and default scenario

Given the following Test of `sample-combined`:
```java
@CitrusTest
public void testInterveningRequest() {
variable("correlationId", "citrus:randomNumber(10)");

//GoodNightScenario
http().client(simulatorClient)
.send()
.post("goodnight")
.payload("" +
"Go to sleep!" +
"")
.header("x-correlationid", "${correlationId}");

http().client(simulatorClient)
.receive()
.response(HttpStatus.OK)
.payload("" +
"Good Night!" +
"");

//DefaultScenario
http().client(simulatorClient)
.send()
.post()
.payload("In between!");

http().client(simulatorClient)
.receive()
.response(HttpStatus.OK)
.payload(defaultResponse);

//GoodNightScenario
http().client(simulatorClient)
.send()
.post()
.payload("In between!")
.header("x-correlationid", "${correlationId}");

http().client(simulatorClient)
.receive()
.response(HttpStatus.OK)
.payload("In between!");

//Should be DefaultScenario (Race condition here)
http().client(simulatorClient)
.send()
.put("goodnight")
.payload("In between!")
.header("x-correlationid", "${correlationId}");

http().client(simulatorClient)
.receive()
.response(HttpStatus.OK)
.payload(defaultResponse);
}
```

If the test runs "fast enough", the `GoodNightScenario` is still active in the `CorrelationHandlerRegistry`, because `doFinally().actions(builder.stop())` of the `ScenarioDesigner`, containing the `StopCorrelationHandlerAction` to stop the scenario, has not been finished, until the next request, that matches the `x-correlationid` header condition, arrives.

BR,
Sven

Start with the sample-combined test and trace the GoodNightScenario through CorrelationHandlerRegistry and ScenarioDesigner, especially the StopCorrelationHandlerAction in doFinally(). Reproduce the fast request sequence and verify that the scenario is no longer active before the following request is matched as DefaultScenario.

Written by the indexing model from the issue text.