protected void close() {
    close(true, false);
  }
Closes the proxy. This method checks the message queue for any unprocessed messages and
processes them for MAXIMUM_SHUTDOWN_PEEKS.

@see CacheClientProxy#MAXIMUM_SHUTDOWN_PEEKS
geode-core/src/main/java/org/apache/geode/internal/cache/tier/sockets/CacheClientProxy.java