Add spec for GroupScore model

spec/models/group_score_spec.rb

@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe GroupScore, type: :model do
+  describe 'association' do
+    it { should belong_to :team }
+  end
+end

spec/models/team_spec.rb

@@ -9,5 +9,6 @@ RSpec.describe Team, type: :model do
 
   describe 'association' do
     it { should belong_to :tournament }
+    it { should have_one :group_score }
   end
 end