DEV: Minor review fixes and fix bookmark spec logging (#9045)

As per:

https://review.discourse.org/t/fix-never-allow-custom-emoji-to-be-marked-secure-8965/9072
https://review.discourse.org/t/feature-improving-bookmarks-part-2-topic-bookmarking-8954/9038

app/models/post.rb

@@ -918,8 +918,8 @@ class Post < ActiveRecord::Base
       if SiteSetting.secure_media?
         Upload.where(
           id: upload_ids, access_control_post_id: nil
-        ).where.not(
-          id: CustomEmoji.pluck(:upload_id)
+        ).where(
+          'id NOT IN (SELECT upload_id FROM custom_emojis)'
         ).update_all(
           access_control_post_id: self.id
         )

spec/tasks/bookmarks_spec.rb

@@ -17,8 +17,14 @@ RSpec.describe "bookmarks tasks" do
     create_post_actions_and_existing_bookmarks
   end
 
+  def invoke_task(args = nil)
+    capture_stdout do
+      Rake::Task['bookmarks:sync_to_table'].invoke(args)
+    end
+  end
+
   it "migrates all PostActions" do
-    Rake::Task['bookmarks:sync_to_table'].invoke
+    invoke_task
 
     expect(Bookmark.all.count).to eq(3)
   end
@@ -26,14 +32,14 @@ RSpec.describe "bookmarks tasks" do
   it "does not create bookmarks that already exist in the bookmarks table for a user" do
     Fabricate(:bookmark, user: user1, post: post1)
 
-    Rake::Task['bookmarks:sync_to_table'].invoke
+    invoke_task
 
     expect(Bookmark.all.count).to eq(3)
     expect(Bookmark.where(post: post1, user: user1).count).to eq(1)
   end
 
   it "respects the sync_limit if provided and stops creating bookmarks at the limit (so this can be run progrssively" do
-    Rake::Task['bookmarks:sync_to_table'].invoke(1)
+    invoke_task(1)
     expect(Bookmark.all.count).to eq(1)
   end