AO3-6204 Add test for attempting to remove a normal users pseud

spec/controllers/admin/user_creations_controller_spec.rb

@@ -300,6 +300,7 @@
 
       context "with a pseud parameter by a normal user" do
         subject { put :remove_pseud, params: { id: work.id, pseuds: [user.default_pseud.id] } }
+        let(:work) { create(:work, authors: [user.default_pseud]) }
 
         it "does not modify the work" do
           expect do