v0.16.8 Fix TIFF image support bug

gossamer_forums.rb

@@ -1,5 +1,5 @@
 # gossamer threads migration-import code
-# v0.16.7
+# v0.16.8
 
 require 'mysql2'
 require 'open-uri'
@@ -455,6 +455,7 @@ class GossamerForumsImporter < ImportScripts::Base
           next
         end
         temp_file.close
+        temp_file.unlink
         temp_file = File.open(converted_tiff_to_png_path)
       end
 
@@ -515,7 +516,7 @@ class GossamerForumsImporter < ImportScripts::Base
 
       # Clean up temporary files
       temp_file.close
-      temp_file.unlink
+      temp_file.unlink if temp_file.is_a?(Tempfile)
       resized_temp_file.close
       resized_temp_file.unlink
     end