Fix CurrentUser issue with tests

For some tests, the current user wasn't set by the time the CurrentUser
variable was used in several of the models.

app/models/post_vote.rb

@@ -25,7 +25,7 @@ class PostVote < ApplicationRecord
   end
 
   def initialize_attributes
-    self.user_id ||= CurrentUser.user.id
+    self.user_id ||= CurrentUser.id
 
     if vote == "up"
       self.score = 1

app/models/wiki_page.rb

@@ -189,12 +189,12 @@ class WikiPage < ApplicationRecord
 
   def merge_version?
     prev = versions.last
-    prev && prev.updater_id == CurrentUser.user.id && prev.updated_at > 1.hour.ago
+    prev && prev.updater_id == CurrentUser.id && prev.updated_at > 1.hour.ago
   end
 
   def create_new_version
     versions.create(
-      :updater_id => CurrentUser.user.id,
+      :updater_id => CurrentUser.id,
       :updater_ip_addr => CurrentUser.ip_addr,
       :title => title,
       :body => body,