Use respond_to? instead of try

Usually when we use `try` we actually mean `try!`, which is the same as
the safe navigation operator. However, there are a few cases where we
actually mean to execute a method if the object responds to that method.

In those cases using `try` would actually be OK, but in order to avoid
confusion as to whether we mean to check for `respond_to?` or we mean to
use safe navigation, I'm removing all usages of `try`.

app/helpers/welcome_helper.rb

@@ -25,7 +25,7 @@ module WelcomeHelper
   end
 
   def calculate_image_path(recommended, image_default)
-    if recommended.try(:image) && recommended.image.present? && recommended.image.attachment.exists?
+    if recommended.respond_to?(:image) && recommended.image.present? && recommended.image.attachment.exists?
       recommended.image.attachment.send("url", :medium)
     elsif image_default.present?
       image_default

app/models/comment.rb

@@ -120,7 +120,7 @@ class Comment < ApplicationRecord
   end
 
   def call_after_commented
-    commentable.try(:after_commented)
+    commentable.after_commented if commentable.respond_to?(:after_commented)
   end
 
   def self.body_max_length

app/models/concerns/notifiable.rb

@@ -29,8 +29,8 @@ module Notifiable
 
   def check_availability(resource)
     resource.present? &&
-      resource.try(:hidden_at).nil? &&
-      resource.try(:retired_at).nil?
+      !(resource.respond_to?(:hidden?) && resource.hidden?) &&
+      !(resource.respond_to?(:retired?) && resource.retired?)
   end
 
   def linkable_resource