Remove unused import in the SmbMessageHandler

Author: artembilan

spring-integration-smb/src/main/java/org/springframework/integration/smb/outbound/SmbMessageHandler.java

@@ -22,7 +22,6 @@
 import org.springframework.integration.smb.session.SmbRemoteFileTemplate;
 
 import jcifs.smb.SmbFile;
-import reactor.core.publisher.Mono;
 
 /**
  * The SMB specific {@link FileTransferringMessageHandler} extension. Based on the