FIX: default_tags_muted site setting won't have tag ids.

Instead it only have list of tag names separated by comma.
89fcb75af2

lib/topic_query.rb

@@ -917,7 +917,8 @@ class TopicQuery
     if user.present?
       muted_tag_ids = TagUser.lookup(user, :muted).pluck(:tag_id)
     else
-      muted_tag_ids = SiteSetting.default_tags_muted.split("|").map(&:to_i)
+      muted_tag_names = SiteSetting.default_tags_muted.split("|")
+      muted_tag_ids = Tag.where(name: muted_tag_names).pluck(:id)
     end
 
     if muted_tag_ids.blank?

spec/components/topic_query_spec.rb

@@ -286,7 +286,7 @@ describe TopicQuery do
 
       before do
         SiteSetting.remove_muted_tags_from_latest = 'always'
-        SiteSetting.default_tags_muted = tag.id.to_s
+        SiteSetting.default_tags_muted = tag.name
       end
 
       it 'removes default muted tag topics for anonymous users' do