artists: reduce queries in artist summaries.

Avoid a few queries when searching for single artist tags.

app/models/artist.rb

@@ -386,14 +386,6 @@ class Artist < ApplicationRecord
   end
 
   module TagMethods
-    def has_tag_alias?
-      TagAlias.active.exists?(["antecedent_name = ?", name])
-    end
-
-    def tag_alias_name
-      TagAlias.active.find_by_antecedent_name(name).consequent_name
-    end
-
     def category_name
       Tag.category_for(name)
     end

app/views/artists/_summary.html.erb

@@ -3,16 +3,13 @@
   <li><strong>Status</strong> <%= artist.status %></li>
 
   <% if !artist.is_banned? || CurrentUser.is_member? %>
-    <% if artist.has_tag_alias? %>
-      <li><strong>Tag Alias</strong> <%= artist.tag_alias_name %></li>
-    <% end %>
     <% if artist.other_names.present? %>
       <li><strong>Other Names</strong> <%= link_to_artists(artist.other_names) %></li>
     <% end %>
     <% if artist.group_name.present? %>
       <li><strong>Group</strong> <%= link_to_artist(artist.group_name) %></li>
     <% end %>
-    <% if artist.members.any? %>
+    <% if artist.members.present? %>
       <li><strong>Members</strong> <%= link_to_artists(artist.members.map(&:name)) %></li>
     <% end %>
     <% if artist.domains.any? %>
@@ -23,7 +20,7 @@
         <% end %>
       </ul>
     <% end %>
-    <% if artist.urls.any? %>
+    <% if artist.urls.present? %>
       <li><strong>URLs</strong></li>
       <ul>
         <% artist.urls.each do |url| %>