content nil and empty

Signed-off-by: RAMELLA Sebastien <[email protected]>

Author: mekhalleh

modules/auxiliary/fileformat/maldoc_in_pdf_polyglot.rb

@@ -197,7 +197,7 @@ def rand_pdfheader
 
   def run
     content = File.read(datastore['FILENAME'])
-    if content.nil? || content.empty?
+    if content&.empty?
       fail_with(Failure::BadConfig, 'The MHT file content is empty')
     end