Adds cleanup option in documentation

Author: msutovsky-r7

documentation/modules/exploit/windows/local/linqpad_deserialization.md

@@ -15,6 +15,11 @@ Steps:
 
 ## Options
 
+### cleanup
+
+Enable cleanup of malicious file. The module will replace cache filewith malicious content. If `cleanup` is enabled, after successful execution, the module will remove malicious cache file. The original file will be restored upon re-execution of Linqpad.
+
+
 ### cache\_path
 
 The parameter sets path for folder, where vulnerable cache file is present. This is crucial part of the exploit as the folder can be used to identify whether the current version is vulnerable and the payload delivery is performed through cache file.