Return finding_uuid with vulnerability_feedback

The finding_uuid field will be returned in the response of the
vulnerability_feedback endpoint

app/serializers/vulnerabilities/feedback_entity.rb

@@ -12,6 +12,7 @@ class Vulnerabilities::FeedbackEntity < Grape::Entity
     expose :comment_timestamp
     expose :comment_author, using: UserEntity
   end
+  expose :finding_uuid
 
   expose :pipeline, if: -> (feedback, _) { feedback.pipeline.present? } do
     expose :id do |feedback|

ee/changelogs/unreleased/292800-return-the-uuid-attribute-of-the-finding-records-in-the-respons.yml

+---
+title: Return the finding_uuid attribute in the response of vulnerability_feedback
+  endpoint
+merge_request: 49745
+author:
+type: changed

ee/spec/fixtures/api/schemas/vulnerability_feedback.json

@@ -36,7 +36,8 @@
     },
     "project_fingerprint": { "type": "string" },
     "branch": { "type": ["string", "null"] },
-    "destroy_vulnerability_feedback_dismissal_path": { "type": "string" }
+    "destroy_vulnerability_feedback_dismissal_path": { "type": "string" },
+    "finding_uuid": { "type": ["string", "null"] }
   },
   "additionalProperties": false
 }

ee/spec/serializers/vulnerabilities/feedback_entity_spec.rb

@@ -167,4 +167,21 @@ RSpec.describe Vulnerabilities::FeedbackEntity do
       expect(subject[:comment_details]).to include(:comment_author)
     end
   end
+
+  context 'when finding_uuid is not present' do
+    let(:feedback) { build(:vulnerability_feedback, :issue, project: project) }
+
+    it 'has a nil finding_uuid' do
+      expect(subject[:finding_uuid]).to be_nil
+    end
+  end
+
+  context 'when finding_uuid is present' do
+    let_it_be(:finding) { create(:vulnerabilities_finding) }
+    let(:feedback) { create(:vulnerability_feedback, finding_uuid: finding.uuid, project: project) }
+
+    it 'exposes finding_uuid' do
+      expect(subject[:finding_uuid]).to eq(finding.uuid)
+    end
+  end
 end