tests: fix broken tests.

test/unit/post_query_builder_test.rb

@@ -327,13 +327,6 @@ class PostQueryBuilderTest < ActiveSupport::TestCase
       assert_tag_match(posts, "ordpool:test")
     end
 
-    should "return posts for the ordpool:<name> metatag for a series pool containing duplicate posts" do
-      posts = create_list(:post, 2)
-      pool = create(:pool, name: "test", category: "series", post_ids: [posts[0].id, posts[1].id, posts[1].id])
-
-      assert_tag_match([posts[0], posts[1], posts[1]], "ordpool:test")
-    end
-
     should "return posts for the parent:<N> metatag" do
       parent = create(:post)
       child = create(:post, tag_string: "parent:#{parent.id}")