Fix rapid7#5499, small fix for line clearing

Author: wvu

lib/msf/ui/console/driver.rb

@@ -547,7 +547,7 @@ def on_startup(opts = {})
 
     if $msf_spinner_thread
       $msf_spinner_thread.kill
-      $stderr.print "\r" + (" " * 60) + "\n"
+      $stderr.print "\r" + (" " * 50) + "\n"
     end
 
     run_single("banner") unless opts['DisableBanner']