Merge branch '348264-Expose-finished_at-in-job-details-JSON' into 'master'

Expose finished_at in job details JSON

See merge request gitlab-org/gitlab!76668

app/serializers/build_details_entity.rb

 # frozen_string_literal: true
 
 class BuildDetailsEntity < Ci::JobEntity
-  expose :coverage, :erased_at, :duration
+  expose :coverage, :erased_at, :finished_at, :duration
   expose :tag_list, as: :tags
   expose :has_trace?, as: :has_trace
   expose :stage

spec/serializers/build_details_entity_spec.rb

@@ -29,7 +29,7 @@ RSpec.describe BuildDetailsEntity do
     end
 
     it 'contains the needed key value pairs' do
-      expect(subject).to include(:coverage, :erased_at, :duration)
+      expect(subject).to include(:coverage, :erased_at, :finished_at, :duration)
       expect(subject).to include(:runner, :pipeline)
       expect(subject).to include(:raw_path, :new_issue_path)
     end