SseEventSourceImpl should not close http engine

Invoking close() method on an org.jboss.resteasy.plugins.providers.sse.client.SseEventSourceImpl instance
should not close the javax.ws.rs.client.Client instance bounded to the Sse javax.ws.rs.client.WebTarget provided by the user.

Suppose that as advised by the spec a user decide to create only one javax.ws.rs.client.Client instance for its whole application using
connection poooling feature provided by HttpClient for example. Then if he decides to consume a Sse stream using org.jboss.resteasy.plugins.providers.sse.client.SseEventSourceImpl
once he will invoke SseEventSourceImpl.close() its Client instance will be closed too and not usable any longer by its application.