XatkitException when receiving an Event not used in the execution model

[gdaniel]

Xatkit cannot build the EventInstance associated to the received event if this event is not used in the execution model. This is not surprising since only events that are used in the execution model are loaded in the registry, but the log should only contain a warning and not an error with a stack trace.

So far this issue has only be found with the Github platform, but it may be related to the Xatkit Runtime component and how received payloads are matched by the Xatkit server.

Below is an example stack trace when a non-registered Issue_Closed event is received.

[ERROR] 01:57:40,990 - null
com.xatkit.core.XatkitException: Cannot build the EventInstance, the EventDefinition Issue_Closed does not exist
       at com.xatkit.core.platform.io.EventInstanceBuilder.build(EventInstanceBuilder.java:178)
       at com.xatkit.core.platform.io.JsonEventMatcher.createEventInstance(JsonEventMatcher.java:237)
       at com.xatkit.core.platform.io.JsonEventMatcher.match(JsonEventMatcher.java:194)
       at com.xatkit.plugins.github.platform.io.GithubWebhookEventProvider.lambda$createRestHandler$0(GithubWebhookEventProvider.java:90)
       at com.xatkit.core.server.RestHandlerFactory$1.handleParsedContent(RestHandlerFactory.java:50)
       at com.xatkit.core.server.RestHandlerFactory$1.handleParsedContent(RestHandlerFactory.java:46)
       at com.xatkit.core.server.RestHandler.handleContent(RestHandler.java:94)
       at com.xatkit.core.server.XatkitServer.notifyRestHandler(XatkitServer.java:291)
       at com.xatkit.core.server.HttpHandler.handle(HttpHandler.java:195)
       at org.apache.http.protocol.HttpService.doService(HttpService.java:437)
       at org.apache.http.protocol.HttpService.handleRequest(HttpService.java:342)
       at org.apache.http.impl.bootstrap.Worker.run(Worker.java:66)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
       at java.lang.Thread.run(Unknown Source)

This issue has been reported by @jcabot on the Github bot example.