Remove legacy test example in CI/CD activity limit class

spec/ee/spec/lib/ee/gitlab/ci/pipeline/chain/limit/activity_spec.rb

@@ -40,11 +40,6 @@ describe EE::Gitlab::Ci::Pipeline::Chain::Limit::Activity do
     it 'sets a valid failure reason' do
       expect(pipeline.activity_limit_exceeded?).to be true
     end
-
-    it 'appends validation error' do
-      expect(pipeline.errors.to_a)
-        .to include 'Active pipelines limit exceeded by 2 pipelines!'
-    end
   end
 
   context 'when pipeline size limit is not exceeded' do