Fix "warning: `*' interpreted as argument prefix"

Author: kamipo

activestorage/lib/active_storage/previewer.rb

@@ -55,7 +55,7 @@ def download_blob_to(file)
       #   end
       def draw(*argv) # :doc:
         Tempfile.open("output") do |file|
-          capture *argv, to: file
+          capture(*argv, to: file)
           yield file
         end
       end