Land rapid7#4578, @dlanner's fix for rails_secret_deserialization

Author: jhart-r7

modules/exploits/multi/http/rails_secret_deserialization.rb

@@ -234,7 +234,7 @@ def exploit
       'method' => datastore['HTTP_METHOD'],
     }, 25)
     if res && !res.get_cookies.empty?
-      match = res.get_cookies.match(/([_A-Za-z0-9]+)=([A-Za-z0-9%]*)--([0-9A-Fa-f]+); /)
+      match = res.get_cookies.match(/([_A-Za-z0-9]+)=([A-Za-z0-9%]*)--([0-9A-Fa-f]+);/)
     end
 
     if match