Story: description_or_story_text should return plaintext

Co-authored-by: joshua stein <[email protected]>

Author: k0kubun

benchmarks/lobsters/app/models/story.rb

@@ -503,7 +503,7 @@ def description_or_story_text(chars = 0)
       s = s.to_s[0, chars].gsub(/ [^ ]*\z/, "")
     end
 
-    HtmlEncoder.encode(s.to_s)
+    HtmlEncoder.decode(s.to_s)
   end
 
   def domain_search_url