Add a default status const to common status concern

app/models/concerns/has_status.rb

 module HasStatus
   extend ActiveSupport::Concern
+  DEFAULT_STATUS = 'created'
   AVAILABLE_STATUSES = %w[created pending running success failed canceled skipped]
   STARTED_STATUSES = %w[running success failed skipped]
   ACTIVE_STATUSES = %w[pending running]

lib/gitlab/ci/status/factory.rb

@@ -5,7 +5,7 @@ module Gitlab
         def initialize(subject, user)
           @subject = subject
           @user = user
-          @status = subject.status || :created
+          @status = subject.status || HasStatus::DEFAULT_STATUS
         end
         def fabricate!

spec/models/concerns/has_status_spec.rb

@@ -219,4 +219,10 @@ describe HasStatus do
       end
     end
   end
+
+  describe '::DEFAULT_STATUS' do
+    it 'is a status created' do
+      expect(described_class::DEFAULT_STATUS).to eq 'created'
+    end
+  end
 end