Reducing subtle duplication of effort/logic

Prior to this commit, when we change attributes for a user we might
resave each article.  The purpose of the resave is to update some of the
cached attributes of an article.

This removes some redundant code.  The following removed code has
an `article.save` call.  Which, the callbacks in the article (see below)
already clear the cache.

```ruby
def resave_articles
  articles.find_each do |article|
    if article.path
      cache_bust = EdgeCache::Bust.new
      cache_bust.call(article.path)
      cache_bust.call("#{article.path}?i=i")
    end
    article.save
  end
end
```

https://github.com/forem/forem/blob/8e6981aac59e86a9a2c69db1e50fb1119f509c8d/app/models/article.rb#L164

https://github.com/forem/forem/blob/8e6981aac59e86a9a2c69db1e50fb1119f509c8d/app/models/article.rb#L881-L888

This was discovered in triaging #17041

app/models/user.rb

@@ -497,17 +497,6 @@ def a_sustaining_member?
     monthly_dues.positive?
   end
 
-  def resave_articles
-    articles.find_each do |article|
-      if article.path
-        cache_bust = EdgeCache::Bust.new
-        cache_bust.call(article.path)
-        cache_bust.call("#{article.path}?i=i")
-      end
-      article.save
-    end
-  end
-
   def profile_image_90
     profile_image_url_for(length: 90)
   end

app/workers/users/resave_articles_worker.rb

@@ -8,7 +8,7 @@ def perform(user_id)
       user = User.find_by(id: user_id)
       return unless user
 
-      user.resave_articles
+      user.articles.find_each(&:save)
     end
   end
 end