[ci] Improve Kiwi::Repository validations spec

src/api/spec/models/kiwi/repository_spec.rb

@@ -75,7 +75,7 @@
       end
     end
 
-    it { is_expected.to validate_inclusion_of(:repo_type).in_array(%w(apt-deb rpm-dir rpm-md yast2)) }
+    it { is_expected.to validate_inclusion_of(:repo_type).in_array(Kiwi::Repository::REPO_TYPES) }
     it { is_expected.to validate_numericality_of(:priority).is_greater_than_or_equal_to(0).is_less_than(100) }
     it { is_expected.to validate_numericality_of(:order).is_greater_than_or_equal_to(1) }
     it { is_expected.to allow_value(nil).for(:imageinclude) }